Method and device for transmitting and receiving wireless signal in wireless communication system

ABSTRACT

The present invention relates to a wireless communication system and, particularly, to a method and a device therefor, the method comprising the steps of: receiving a first DCI including a counter-DAI and slot group indication information, wherein the counter-DAI indicates a scheduling order in a slot group, and the slot group indication information indicates a first slot group from among a plurality of slot groups; receiving downlink data on the basis of the first DCI; receiving a second DCI including a total-DAI and requiring A/N feedback for the first slot group from among the plurality of slot groups, wherein the total-DAI indicates the total number of schedulings in a slot group; and transmitting uplink control information including A/N information about the first slot group on the basis of the counter-DAI and the total-DAI.

TECHNICAL FIELD

The present disclosure relates to a wireless communication system and,more particularly, to a method and device for transmitting and receivingwireless signals.

BACKGROUND

Wireless access systems have been widely deployed to provide varioustypes of communication services such as voice or data. In general, awireless access system is a multiple access system that supportscommunication of multiple users by sharing available system resources (abandwidth, transmission power, etc.) among them. For example, multipleaccess systems include a code division multiple access (CDMA) system, afrequency division multiple access (FDMA) system, a time divisionmultiple access (TDMA) system, an orthogonal frequency division multipleaccess (OFDMA) system, and a single carrier frequency division multipleaccess (SC-FDMA) system.

SUMMARY

The object of the present disclosure is to provide a method ofefficiently transmitting and receiving wireless signals and devicetherefor.

It will be appreciated by persons skilled in the art that the objectsthat could be achieved with the present disclosure are not limited towhat has been particularly described hereinabove and the above and otherobjects that the present disclosure could achieve will be more clearlyunderstood from the following detailed description.

In one aspect of the present disclosure, a method of transmitting asignal by a wireless device in a wireless communication system isprovided. The method may include: receiving first downlink controlinformation (DCI) including a counter downlink assignment index(counter-DAI) and slot group indication information, wherein thecounter-DAI indicates a scheduling order in a slot group and the slotgroup indication information indicates a first slot group among aplurality of slot groups; receiving downlink data based on the firstDCI; receiving second DCI including a total-DAI and requestingacknowledgment/negative acknowledgement (A/N) feedback for the firstgroup among the plurality of slot groups, wherein the total-DAIindicates the total number of times that scheduling is performed in aslot group; and transmitting uplink control information including A/Ninformation for the first slot group based on the counter-DAI and thetotal-DAI.

In another aspect of the present disclosure, a wireless device for usein a wireless communication system is provided. The wireless device mayinclude a memory and a processor. The processor may be configured to:receive first DCI including a counter-DAI and slot group indicationinformation, wherein the counter-DAI indicates a scheduling order in aslot group and the slot group indication information indicates a firstslot group among a plurality of slot groups; receive downlink data basedon the first DCI; receive second DCI including a total-DAI andrequesting A/N feedback for the first group among the plurality of slotgroups, wherein the total-DAI indicates the total number of times thatscheduling is performed in a slot group; and transmit uplink controlinformation including A/N information for the first slot group based onthe counter-DAI and the total-DAI.

Preferably, the size of the A/N information for the first slot group maybe determined based on the total-DAI, and A/N information may bearranged in the order of values of the counter-DAI in the A/Ninformation for the first slot group.

Preferably, the second DCI may include DCI scheduling a physicaldownlink shared channel (PDSCH), and the second DCI may include firstinformation about the index of a slot group including the PDSCH andsecond information indicating that the first slot group is a slot groupfor which A/N feedback is required.

Preferably, the slot group indicated by the first information may bedifferent from the first slot group.

Preferably, the second DCI may further include a total-DAI for the slotgroup including the PDSCH.

Preferably, the DCI may further include third information about thetransmission time of the uplink control information.

Preferably, the uplink control information may be transmitted in anunlicensed band (U-band).

Preferably, the wireless device may include an autonomous drivingvehicle configured to communicate at least with a terminal, a network,and another autonomous driving vehicle other than the wireless device.

According to the present disclosure, wireless signal transmission andreception may be efficiently performed in a wireless communicationsystem.

It will be appreciated by persons skilled in the art that the effectsthat could be achieved with the present disclosure are not limited towhat has been particularly described hereinabove and other advantages ofthe present disclosure will be more clearly understood from thefollowing detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention, illustrate embodiments of the presentdisclosure and together with the description serve to explain theprinciple of the present disclosure. In the drawings:

FIG. 1 illustrates physical channels and a general signal transmissionmethod using the physical channels in a 3^(rd) generation partnershipproject (3GPP) system as an exemplary wireless communication system;

FIG. 2 illustrates a radio frame structure;

FIG. 3 illustrates a resource grid during the duration of a slot;

FIG. 4 illustrates a self-contained slot structure;

FIG. 5 illustrates mapping of physical channels in a self-containedslot;

FIG. 6 illustrates an acknowledgment/negative acknowledgment (ACK/NACK)transmission process;

FIG. 7 illustrates a physical uplink shared channel (PUSCH) transmissionprocess;

FIG. 8 illustrates exemplary multiplexing of control information in aPUSCH;

FIG. 9 illustrates a wireless communication system supporting anunlicensed band;

FIG. 10 illustrates an exemplary method of occupying resources in anunlicensed band;

FIG. 11 is a flowchart illustrating a Type 1 channel access procedure(CAP) of a user equipment (UE) for uplink (UL) signal transmission;

FIGS. 12 to 15 illustrate signal transmission according to examples ofthe present disclosure;

FIG. 16 illustrates an initial access procedure applicable to thepresent disclosure; and

FIGS. 17 to 20 illustrate a communication system 1 applied to thepresent disclosure.

DETAILED DESCRIPTION

The following technology may be used in various wireless access systemssuch as code division multiple access (CDMA), frequency divisionmultiple access (FDMA), time division multiple access (TDMA), orthogonalfrequency division multiple access (OFDMA), single carrier frequencydivision multiple access (SC-FDMA), and so on. CDMA may be implementedas a radio technology such as universal terrestrial radio access (UTRA)or CDMA2000. TDMA may be implemented as a radio technology such asglobal system for mobile communications (GSM)/general packet radioservice (GPRS)/enhanced data rates for GSM evolution (EDGE). OFDMA maybe implemented as a radio technology such as institute of electrical andelectronics engineers (IEEE) 802.11 (wireless fidelity (Wi-Fi)), IEEE802.16 (worldwide interoperability for microwave access (WiMAX)), IEEE802.20, evolved UTRA (E-UTRA), and so on. UTRA is a part of universalmobile telecommunications system (UMTS). 3^(rd) generation partnershipproject (3GPP) long term evolution (LTE) is a part of evolved UMTS(E-UMTS) using E-UTRA, and LTE-advanced (LTE-A) is an evolution of 3GPPLTE. 3GPP new radio or new radio access technology (NR) is an evolvedversion of 3GPP LTE/LTE-A.

As more and more communication devices require larger communicationcapacities, the need for enhanced mobile broadband communicationrelative to the legacy radio access technologies (RATs) has emerged.Massive machine type communication (MTC) providing various services tointer-connected multiple devices and things at any time in any place isone of significant issues to be addressed for next-generationcommunication. A communication system design in which services sensitiveto reliability and latency are considered is under discussion as well.As such, the introduction of the next-generation radio access technology(RAT) for enhanced mobile broadband communication (eMBB), massive MTC(mMTC), and ultra-reliable and low latency communication (URLLC) isbeing discussed. For convenience, this technology is called NR or NewRAT in the present disclosure.

While the following description is given in the context of a 3GPPcommunication system (e.g., NR) for clarity, the technical spirit of thepresent disclosure is not limited to the 3GPP communication system.

In a wireless access system, a user equipment (UE) receives informationfrom a base station (BS) on DL and transmits information to the BS onUL. The information transmitted and received between the UE and the BSincludes general data and various types of control information. Thereare many physical channels according to the types/usages of informationtransmitted and received between the BS and the UE.

FIG. 1 illustrates physical channels and a general signal transmissionmethod using the physical channels in a 3GPP system.

When a UE is powered on or enters a new cell, the UE performs initialcell search (S101). The initial cell search involves acquisition ofsynchronization to a BS. For this purpose, the UE receives asynchronization signal block (SSB) from the BS. The SSB includes aprimary synchronization signal (PSS), a secondary synchronization signal(SSS), and a physical broadcast channel (PBCH). The UE synchronizes itstiming to the BS and acquires information such as a cell identifier (ID)based on the PSS/SSS. Further, the UE may acquire information broadcastin the cell by receiving the PBCH from the BS. During the initial cellsearch, the UE may also monitor a DL channel state by receiving adownlink reference signal (DL RS).

After the initial cell search, the UE may acquire more detailed systeminformation by receiving a physical downlink control channel (PDCCH) andreceiving a physical downlink shared channel (PDSCH) based oninformation in the PDCCH (S102).

Subsequently, to complete connection to the BS, the UE may perform arandom access procedure with the BS (S103 to S106). Specifically, the UEmay transmit a preamble on a physical random access channel (PRACH)(S103) and may receive a PDCCH and a random access response (RAR) forthe preamble on a PDSCH corresponding to the PDCCH (S104). The UE maythen transmit a physical uplink shared channel (PUSCH) by usingscheduling information in the RAR (S105), and perform a contentionresolution procedure including reception of a PDCCH and a PDSCH signalcorresponding to the PDCCH (S106).

After the above procedure, the UE may receive a PDCCH and/or a PDSCHfrom the BS (S107) and transmit a physical uplink shared channel (PUSCH)and/or a physical uplink control channel (PUCCH) to the BS (S108), in ageneral UL/DL signal transmission procedure. Control information thatthe UE transmits to the BS is generically called uplink controlinformation (UCI). The UCI includes a hybrid automatic repeat andrequest acknowledgement/negative acknowledgement (HARQ-ACK/NACK), ascheduling request (SR), channel state information (CSI), and so on. TheCSI includes a channel quality indicator (CQI), a precoding matrix index(PMI), a rank indication (RI), and so on. In general, UCI is transmittedon a PUCCH. However, if control information and data should betransmitted simultaneously, the control information and the data may betransmitted on a PUSCH. In addition, the UE may transmit the UCIaperiodically on the PUSCH, upon receipt of a request/command from anetwork.

FIG. 2 illustrates a radio frame structure. In NR, UL and DLtransmissions are configured in frames. Each radio frame has a length of10 ms and is divided into two 5-ms half-frames. Each half-frame isdivided into five 1-ms subframes. A subframe is divided into one or moreslots, and the number of slots in a subframe depends on a subcarrierspacing (SCS). Each slot includes 12 or 14 OFDM(A) symbols according toa cyclic prefix (CP). When a normal CP is used, each slot includes 14OFDM symbols. When an extended CP is used, each slot includes 12 OFDMsymbols. A symbol may include an OFDM symbol (or a CP-OFDM symbol) andan SC-FDMA symbol (or a discrete Fourier transform-spread-OFDM(DFT-s-OFDM) symbol).

Table 1 exemplarily illustrates that the number of symbols per slot, thenumber of slots per frame, and the number of slots per subframe varyaccording to SCSs in a normal CP case.

TABLE 1 SCS (15*2{circumflex over ( )}u) N^(slot) _(symb) N^(frame, u)_(slot) N^(subframe, u) _(slot) 15 KHz (u = 0) 14 10 1 30 KHz (u = 1) 1420 2 60 KHz (u = 2) 14 40 4 120 KHz (u = 3)  14 80 8 240 KHz (u = 4)  14160 16 * N^(slot) _(symb): number of symbols in a slot * N^(frame, u)_(slot): number of slots in a frame * N^(subframe, u) _(slot): number ofslots in a subframe

Table 2 illustrates that the number of symbols per slot, the number ofslots per frame, and the number of slots per subframe vary according toSCSs in an extended CP case.

TABLE 2 SCS (15*2{circumflex over ( )}u) N^(slot) _(symb) N^(frame, u)_(slot) N^(subframe, u) _(slot) 60 KHz (u = 2) 12 40 4

The frame structure is merely an example, and the number of subframes,the number of slots, and the number of symbols in a frame may be changedin various manners.

In the NR system, different OFDM(A) numerologies (e.g., SCSs, CPlengths, and so on) may be configured for a plurality of cellsaggregated for one UE. Accordingly, the (absolute time) duration of atime resource (e.g., a subframe, a slot, or a transmission time interval(TTI)) (for convenience, referred to as a time unit (TU)) composed ofthe same number of symbols may be configured differently between theaggregated cells. A symbol may include an OFDM symbol (or CP-OFDMsymbol) and an SC-FDMA symbol (or discrete Fourier transform-spread-OFDM(DFT-s-OFDM) symbol).

FIG. 3 illustrates a resource grid during the duration of one slot. Aslot includes a plurality of symbols in the time domain. For example,one slot includes 14 symbols in a normal CP case and 12 symbols in anextended CP case. A carrier includes a plurality of subcarriers in thefrequency domain. A resource block (RB) may be defined by a plurality of(e.g., 12) consecutive subcarriers in the frequency domain. A bandwidthpart (BWP) may be defined by a plurality of consecutive (physical) RBs((P)RBs) in the frequency domain and correspond to one numerology (e.g.,SCS, CP length, and so on). A carrier may include up to N (e.g., 5)BWPs. Data communication may be conducted in an active BWP, and only oneBWP may be activated for one UE. Each element in a resource grid may bereferred to as a resource element (RE), to which one complex symbol maybe mapped.

FIG. 4 illustrates a structure of a self-contained slot. In the NRsystem, a frame has a self-contained structure in which a DL controlchannel, DL or UL data, a UL control channel, and the like may all becontained in one slot. For example, the first N symbols (hereinafter, DLcontrol region) in the slot may be used to transmit a DL controlchannel, and the last M symbols (hereinafter, UL control region) in theslot may be used to transmit a UL control channel. N and M are integersgreater than or equal to 0. A resource region (hereinafter, a dataregion) that is between the DL control region and the UL control regionmay be used for DL data transmission or UL data transmission. Forexample, the following configuration may be considered. Respectivesections are listed in a temporal order.

1. DL only configuration

2. UL only configuration

3. Mixed UL-DL configuration

-   -   DL region+Guard period (GP)+UL control region    -   DL control region+GP+UL region    -   DL region: (i) DL data region, (ii) DL control region+DL data        region    -   UL region: (i) UL data region, (ii) UL data region+UL control        region

FIG. 5 illustrates mapping of physical channels in a self-containedslot. The PDCCH may be transmitted in the DL control region, and thePDSCH may be transmitted in the DL data region. The PUCCH may betransmitted in the UL control region, and the PUSCH may be transmittedin the UL data region. The GP provides a time gap in the process of theUE switching from the transmission mode to the reception mode or fromthe reception mode to the transmission mode. Some symbols at the time ofswitching from DL to UL within a subframe may be configured as the GP.

Now, a detailed description will be given of physical channels.

The PDCCH delivers DCI. For example, the PDCCH (i.e., DCI) may carryinformation about a transport format and resource allocation of a DLshared channel (DL-SCH), resource allocation information of an uplinkshared channel (UL-SCH), paging information on a paging channel (PCH),system information on the DL-SCH, information on resource allocation ofa higher-layer control message such as an RAR transmitted on a PDSCH, atransmit power control command, information about activation/release ofconfigured scheduling, and so on. The DCI includes a cyclic redundancycheck (CRC). The CRC is masked with various identifiers (IDs) (e.g. aradio network temporary identifier (RNTI)) according to an owner orusage of the PDCCH. For example, if the PDCCH is for a specific UE, theCRC is masked by a UE ID (e.g., cell-RNTI (C-RNTI)). If the PDCCH is fora paging message, the CRC is masked by a paging-RNTI (P-RNTI). If thePDCCH is for system information (e.g., a system information block(SIB)), the CRC is masked by a system information RNTI (SI-RNTI). Whenthe PDCCH is for an RAR, the CRC is masked by a random access-RNTI(RA-RNTI).

The PDCCH may include 1, 2, 4, 8, or 16 control channel elements (CCEs)depending on the aggregation level (AL). The CCE is a logical allocationunit for providing the PDCCH with a predetermined coding rate based onthe state of a radio channel. The PDCCH is transmitted in a controlresource set (CORESET). The CORESET is defined as a set of REGs with agiven numerology (e.g., SCS, CP length, etc.). A plurality of CORESETsfor one UE may overlap in the time/frequency domain. The CORESET may beconfigured by system information (e.g., master information block (MIB))or UE-specific higher layer signaling (e.g., radio resource control(RRC) layer signaling). Specifically, the numbers of RBs and OFDMsymbols (up to three OFDM symbols) in the CORESET may be configured byhigher layer signaling.

To receive/detect the PDCCH, the UE monitors PDCCH candidates. A PDCCHcandidate refers to CCE(s) that the UE should monitor for PDCCHdetection. Each PDCCH candidate is defined by 1, 2, 4, 8, or 16 CCEsdepending on the AL. Here, monitoring includes (blind) decoding of PDCCHcandidates. A set of PDCCH candidates monitored by the UE are defined asa PDCCH search space (SS). The SS may include a common search space(CSS) or a UE-specific search space (USS). The UE may obtain DCI bymonitoring PDCCH candidates in one or more SSs, which are configured byan MIB or higher layer signaling. Each CORESET is associated with one ormore SSs, and each SS is associated with one CORESET. The SS may bedefined based on the following parameters.

-   -   controlResourceSetId: this indicates the CORESET related to the        SS.    -   monitoringSlotPeriodicityAndOffset: this indicates a PDCCH        monitoring periodicity (on a slot basis) and a PDCCH monitoring        period offset (on a slot basis).    -   monitoringSymbolsWithinSlot: this indicates PDCCH monitoring        symbols in a slot (e.g., first symbol(s) in the CORESET).    -   nrofCandidates: this denotes the number of PDCCH candidates for        each AL={1, 2, 4, 8, 16} (one of 0, 1, 2, 3, 4, 5, 6, and 8).    -   An occasion (e.g., time/frequency resource) for monitoring PDCCH        candidates is defined as a PDCCH (monitoring) occasion. One or        more PDCCH (monitoring) occasions may be configured in a slot.

Table 3 shows the characteristics of each SS.

TABLE 3 Search Type Space RNTI Use Case Type0-PDCCH Common SI-RNTI on aprimary SIB cell Decoding Type0A-PDCCH Common SI-RNTI on a primary SIBcell Decoding Type1-PDCCH Common RA-RNTI or TC-RNTI Msg2, Msg4 on aprimary cell decoding in RACH Type2-PDCCH Common P-RNTI on a primarycell Paging Decoding Type3-PDCCH Common INT-RNTI, SFI-RNTI,TPC-PUSCH-RNTI, TPC-PUCCH-RNTI, TPC-SRS-RNTI, C-RNTI, MCS-C-RNTI, orCS-RNTI(s) UE C-RNTI, or MCS-C-RNTI, User specific Specific orCS-RNTI(s) PDSCH decoding

Table 4 shows DCI formats transmitted on the PDCCH.

TABLE 4 DCI format Usage 0_0 Scheduling of PUSCH in one cell 0_1Scheduling of PUSCH in one cell 1_0 Scheduling of PDSCH in one cell 1_1Scheduling of PDSCH in one cell 2_0 Notifying a group of UEs of the slotformat 2_1 Notifying a group of UEs of the PRB(s) and OFDM symbol(s)where UE may assume no transmission is intended for the UE 2_2Transmission of TPC commands for PUCCH and PUSCH 2_3 Transmission of agroup of TPC commands for SRS transmissions by one or more UEs

DCI format 0_0 may be used to schedule a TB-based (or TB-level) PUSCH,and DCI format 0_1 may be used to schedule a TB-based (or TB-level)PUSCH or a code block group (CBG)-based (or CBG-level) PUSCH. DCI format1_0 may be used to schedule a TB-based (or TB-level) PDSCH, and DCIformat 1_1 may be used to schedule a TB-based (or TB-level) PDSCH or aCBG-based (or CBG-level) PDSCH (DL grant DCI). DCI format 0_0/0_1 may bereferred to as UL grant DCI or UL scheduling information, and DCI format1_0/1_1 may be referred to as DL grant DCI or DL scheduling information.DCI format 2_0 is used to deliver dynamic slot format information (e.g.,a dynamic slot format indicator (SFI)) to a UE, and DCI format 2_1 isused to deliver DL pre-emption information to a UE. DCI format 2_0and/or DCI format 2_1 may be delivered to a corresponding group of UEson a group common PDCCH which is a PDCCH directed to a group of UEs.

DCI format 0_0 and DCI format 1_0 may be referred to as fallback DCIformats, whereas DCI format 0_1 and DCI format 1_1 may be referred to asnon-fallback DCI formats. In the fallback DCI formats, a DCI size/fieldconfiguration is maintained to be the same irrespective of a UEconfiguration. In contrast, the DCI size/field configuration variesdepending on a UE configuration in the non-fallback DCI formats.

The PDSCH delivers DL data (e.g., a downlink shared channel (DL-SCH)transport block (TB)) and adopts a modulation scheme such as quadraturephase shift keying (QPSK), 16-ary quadrature amplitude modulation (16QAM), 64-ary QAM (64 QAM), or 256-ary QAM (256 QAM). A TB is encoded toa codeword. The PDSCH may deliver up to two codewords. The codewords areindividually subjected to scrambling and modulation mapping, andmodulation symbols from each codeword are mapped to one or more layers.An OFDM signal is generated by mapping each layer together with a DMRSto resources, and transmitted through a corresponding antenna port.

The PUCCH delivers uplink control information (UCI). The UCI includesthe following information.

-   -   SR: information used to request UL-SCH resources.    -   HARQ-ACK: a response to a DL data packet (e.g., codeword) on the        PDSCH. An HARQ-ACK indicates whether the DL data packet has been        successfully received. In response to a single codeword, a 1-bit        of HARQ-ACK may be transmitted. In response to two codewords, a        2-bit HARQ-ACK may be transmitted. The HARQ-ACK response        includes positive ACK (simply, ACK), negative ACK (NACK),        discontinuous transmission (DTX) or NACK/DTX. The term “HARQ-ACK        is interchangeably used with HARQ ACK/NACK and ACK/NACK.    -   CSI: feedback information for a DL channel. Multiple input        multiple output (MIMO)-related feedback information includes an        RI and a PMI.

Table 5 illustrates exemplary PUCCH formats. PUCCH formats may bedivided into short PUCCHs (Formats 0 and 2) and long PUCCHs (Formats 1,3, and 4) based on PUCCH transmission durations.

TABLE 5 Length in Number PUCCH OFDM symbols of format N_(symb) ^(PUCCH)bits Usage Etc 0 1-2  ≤2 HARQ, SR Sequence selection 1 4-14 ≤2 HARQ,[SR] Sequence modulation 2 1-2  >2 HARQ, CSI, CP-OFDM [SR] 3 4-14 >2HARQ, CSI, DFT-s-OFDM [SR] (no UE multi- plexing) 4 4 14 >2 HARQ, CSI,DFT-s-OFDM [SR] (Pre DFT OCC)

PUCCH format 0 conveys UCI of up to 2 bits and is mapped in asequence-based manner, for transmission. Specifically, the UE transmitsspecific UCI to the BS by transmitting one of a plurality of sequenceson a PUCCH of PUCCH format 0. Only when the UE transmits a positive SR,the UE transmits the PUCCH of PUCCH format 0 in PUCCH resources for acorresponding SR configuration.

PUCCH format 1 conveys UCI of up to 2 bits and modulation symbols of theUCI are spread with an orthogonal cover code (OCC) (which is configureddifferently whether frequency hopping is performed) in the time domain.The DMRS is transmitted in a symbol in which a modulation symbol is nottransmitted (i.e., transmitted in time division multiplexing (TDM)).

PUCCH format 2 conveys UCI of more than 2 bits and modulation symbols ofthe DCI are transmitted in frequency division multiplexing (FDM) withthe DMRS. The DMRS is located in symbols #1, #4, #7, and #10 of a givenRB with a density of 1/3. A pseudo noise (PN) sequence is used for aDMRS sequence. For 2-symbol PUCCH format 2, frequency hopping may beactivated.

PUCCH format 3 does not support UE multiplexing in the same PRBS, andconveys UCI of more than 2 bits. In other words, PUCCH resources ofPUCCH format 3 do not include an OCC. Modulation symbols are transmittedin TDM with the DMRS.

PUCCH format 4 supports multiplexing of up to 4 UEs in the same PRBS,and conveys UCI of more than 2 bits. In other words, PUCCH resources ofPUCCH format 3 include an OCC. Modulation symbols are transmitted in TDMwith the DMRS.

The PUSCH delivers UL data (e.g., UL-shared channel transport block(UL-SCH TB)) and/or UCI based on a CP-OFDM waveform or a DFT-s-OFDMwaveform. When the PUSCH is transmitted in the DFT-s-OFDM waveform, theUE transmits the PUSCH by transform precoding. For example, whentransform precoding is impossible (e.g., disabled), the UE may transmitthe PUSCH in the CP-OFDM waveform, while when transform precoding ispossible (e.g., enabled), the UE may transmit the PUSCH in the CP-OFDMor DFT-s-OFDM waveform. A PUSCH transmission may be dynamicallyscheduled by a UL grant in DCI, or semi-statically scheduled byhigher-layer (e.g., RRC) signaling (and/or Layer 1 (L1) signaling suchas a PDCCH) (configured scheduling or configured grant). The PUSCHtransmission may be performed in a codebook-based or non-codebook-basedmanner.

FIG. 6 illustrates an ACK/NACK transmission process. Referring to FIG.6, the UE may detect a PDCCH in slot #n. The PDCCH includes DLscheduling information (e.g., DCI format 1_0 or DCI format 1_1). ThePDCCH indicates a DL assignment-to-PDSCH offset, K0 and a PDSCH-HARQ-ACKreporting offset, K1. For example, DCI format 1_0 or DCI format 1_1 mayinclude the following information.

-   -   Frequency domain resource assignment: Indicates an RB set        assigned to the PDSCH.    -   Time domain resource assignment: Indicates K0 and the starting        position (e.g. OFDM symbol index) and length (e.g. the number of        OFDM symbols) of the PDSCH in a slot.    -   PDSCH-to-HARQ_feedback timing indicator: Indicates K1.    -   HARQ process number (4 bits): Indicates the HARQ process        identity (ID) of data (e.g., a PDSCH or a TB).

After receiving the PDSCH in slot #(n+K0) according to the schedulinginformation of slot #n, the UE may transmit UCI on the PUCCH in slot#(n+K1). The UCI includes an HARQ-ACK response to the PDSCH. In the casewhere the PDSCH is configured to carry one TB at maximum, the HARQ-ACKresponse may be configured in one bit. In the case where the PDSCH isconfigured to carry up to two TBs, the HARQ-ACK response may beconfigured in two bits if spatial bundling is not configured and in onebit if spatial bundling is configured. When slot #(n+K1) is designatedas an HARQ-ACK transmission timing for a plurality of PDSCHs, UCItransmitted in slot #(n+K1) includes HARQ-ACK responses to the pluralityof PDSCHs.

There are a plurality of parallel DL HARQ processes for DL transmissionsin a BS/UE. In the plurality of parallel HARQ processes, DLtransmissions are continuously performed, while an HARQ feedbackindicating successful or failed reception of a previous DL transmissionis awaited. Each DL HARQ process manages state variables related to thetransmission number of MAC protocol data units (PDUs) in a buffer, anHARQ feedback for a MAC PDU in the buffer, a current redundancy version,and so on. Each HARQ process is identified by an HARQ process ID.

FIG. 7 illustrates an exemplary PUSCH transmission process. Referring toFIG. 7, a UE may detect a PDCCH in slot #n. The PDCCH may include ULscheduling information (e.g., DCI format 0_0 or DCI format 0_1). DCIformat 0_0 and DCI format 0_1 may include the following information.

-   -   Frequency domain resource assignment: Indicates an RB set        allocated to a PUSCH.    -   Time domain resource assignment: Specifies a slot offset K2        indicating the starting position (e.g., symbol index) and length        (e.g., the number of OFDM symbols) of the PUSCH in a slot. The        starting symbol and length of the PUSCH may be indicated by a        start and length indicator value (SLIV), or separately.

The UE may then transmit the PUSCH in slot #(n+K2) according to thescheduling information in slot #n. The PUSCH includes a UL-SCH TB.

FIG. 8 illustrates exemplary multiplexing of UCI in a PUSCH. If aplurality of PUCCH resources overlap with a PUSCH resource in a slot anda PUCCH-PUSCH simultaneous transmission is not configured in the slot,UCI may be transmitted on a PUSCH (UCI piggyback or PUSCH piggyback), asillustrated. In the illustrated case of FIG. 8, an HARQ-ACK and CSI arecarried in a PUSCH resource.

FIG. 9 illustrates an exemplary wireless communication system supportingan unlicensed band applicable to the present disclosure. In thefollowing description, a cell operating in a licensed band (L-band) isdefined as an L-cell, and a carrier of the L-cell is defined as a(DL/UL) LCC. A cell operating in an unlicensed band (U-band) is definedas a U-cell, and a carrier of the U-cell is defined as a (DL/UL) UCC.The carrier/carrier-frequency of a cell may refer to the operatingfrequency (e.g., center frequency) of the cell. A cell/carrier (e.g.,CC) is commonly called a cell.

When carrier aggregation (CA) is supported, one UE may use a pluralityof aggregated cells/carriers to exchange a signal with the BS. When oneUE is configured with a plurality of CCs, one CC may be set to a primaryCC (PCC), and the remaining CCs may be set to secondary CCs (SCCs).Specific control information/channels (e.g., CSS PDCCH, PUCCH) may betransmitted and received only on the PCC. Data may be transmitted andreceived on the PCC/SCC. FIG. 9 (a) shows a case in which the UE and BSexchange signals on both the LCC and UCC (non-stand-alone (NSA) mode).In this case, the LCC and UCC may be set to the PCC and SCC,respectively. When the UE is configured with a plurality of LCCs, onespecific LCC may be set to the PCC, and the remaining LCCs may be set tothe SCC. FIG. 9(a) corresponds to the LAA of the 3GPP LTE system. FIG.9(b) shows a case in which the UE and BS exchange signals on one or moreUCCs with no LCC (stand-alone (SA) mode). In this case, one of the UCCsmay be set to the PCC, and the remaining UCCs may be set to the SCC.Both the NSA mode and SA mode may be supported in the U-band of the 3GPPNR system.

FIG. 10 illustrates an exemplary method of occupying resources in anunlicensed band. According to regional regulations for the U-band, acommunication node in the U-band needs to determine whether acorresponding channel is used by other communication node(s) beforetransmitting a signal. Specifically, the communication node may performcarrier sensing (CS) before transmitting the signal so as to checkwhether the other communication node(s) perform signal transmission.When the other communication node(s) perform no signal transmission, itis said that clear channel assessment (CCA) is confirmed. When a CCAthreshold is predefined or configured by higher layer signaling (e.g.,RRC signaling), if the detected channel energy is higher than the CCAthreshold, the communication node may determine that the channel isbusy. Otherwise, the communication node may determine that the channelis idle. When it is determined that the channel is idle, thecommunication node may start the signal transmission in the UCell. TheWi-Fi standard (802.11ac) specifies a CCA threshold of 62 dBm fornon-Wi-Fi signals and a CCA threshold of −82 dBm for Wi-Fi signals. Thesires of processes described above may be referred to asListen-Before-Talk (LBT) or a channel access procedure (CAP). The LBTmay be interchangeably used with the CAP.

In Europe, two LBT operations are defined: frame based equipment (FBE)and load based equipment (LBE). In FBE, one fixed frame is made up of achannel occupancy time (e.g., 1 to 10 ms), which is a time period duringwhich once a communication node succeeds in channel access, thecommunication node may continue transmission, and an idle periodcorresponding to at least 5% of the channel occupancy time, and CCA isdefined as an operation of observing a channel during a CCA slot (atleast 20 us) at the end of the idle period. The communication nodeperforms CCA periodically on a fixed frame basis. When the channel isunoccupied, the communication node transmits during the channeloccupancy time, whereas when the channel is occupied, the communicationnode defers the transmission and waits until a CCA slot in the nextperiod.

In LBE, the communication node may set q∈{4, 5, . . . , 32} and thenperform CCA for one CCA slot. When the channel is unoccupied in thefirst CCA slot, the communication node may secure a time period of up to(13/32)q ms and transmit data in the time period. When the channel isoccupied in the first CCA slot, the communication node randomly selectsN∈{1, 2, . . . , q}, stores the selected value as an initial value, andthen senses a channel state on a CCA slot basis. Each time the channelis unoccupied in a CCA slot, the communication node decrements thestored counter value by 1. When the counter value reaches 0, thecommunication node may secure a time period of up to (13/32)q ms andtransmit data.

Specifically, a plurality of CAP types may be defined for ULtransmission in the U-band. For example, the UE may perform a Type 1 CAPor a Type 2 CAP for UL signal transmission in the U-band. In general,the UE may perform a CAP configured/indicated by the BS (e.g., Type 1CAP or Type 2 CAP) for the UL signal transmission.

(1) Type 1 UL CAP Method

FIG. 11 is a flowchart illustrating UE's Type 1 CAP operation for ULsignal transmission.

To transmit a signal in the U-band, the UE may initiate a CAP (S1510).The UE may randomly select a backoff counter N within a contentionwindow (CW) according to step 1. In this case, N is set to an initialvalue N_(init) (S1520). N_(init) may have a random value between 0 andCW_(p). If it is determined according to step 4 that the backoff countervalue (N) is 0 (YES in S1530), the UE terminates the CAP (S1532). Then,the UE may perform Tx burst transmission (S1534). If the backoff countervalue is non-zero (NO in S1530), the UE decreases the backoff countervalue by 1 according to step 2 (S1540). The UE checks whether thechannel of U-cell(s) is idle (S1550). If the channel is idle (YES inS1550), the UE checks whether the backoff counter value is 0 (S1530). Onthe contrary, if the channel is not idle in S1550, that is, if thechannel is busy (NO in S1550), the UE checks whether the correspondingchannel is idle for a defer duration T_(d) (longer than or equal to 25usec), which is longer than a slot duration (e.g., 9 usec), according tostep 5 (S1560). If the channel is idle for the defer duration (YES inS1570), the UE may resume the CAP. Here, the defer duration may includea duration of 16 usec and m_(p) consecutive slot durations (e.g., 9usec), which immediately follows the duration of 16 usec. If the channelis busy for the defer duration (NO in S1570), the UE performs step S1560again to check whether the channel is idle for a new defer duration.

Table 6 shows that the values of m_(p), a minimum CW, a maximum CW, amaximum channel occupancy time (MCOT), and allowed CW sizes, which areapplied to the CAP, vary depending on channel access priority classes.

TABLE 6 Channel Access Priority allowed Class (p) m_(p) CW_(min, p)CW_(max, p) T_(N/mcot, p) CW_(p) sizes 1 2 3 7 2 ms {3, 7} 2 2 7 15 4 ms{7, 15} 3 3 15 1023 6 ms or [15, 31, 63, 127, 10 ms 255, 511, 1023} 4 715 1023 6 ms or {15, 31, 63, 127, 10 ms 255, 511, 1023}

The size of a CW applied to the Type 1 UL CAP may be determined invarious ways. For example, the CW size may be adjusted depending onwhether the value of of a new data indicator (NDI) for at least one HARQprocess associated with HARQ_ID_ref, which is the HARQ process ID of aUL-SCH in a predetermined time period (e.g., a reference TU), istoggled. When the UE performs signal transmission using the Type 1 CAPassociated with the channel access priority class p on a carrier, if thevalue of the NDI for the at least one HARQ process associated withHARQ_ID_ref is toggled, the UE may set CW_(p) to CW_(min, p) for everypriority class p∈{1, 2, 3, 4}. Otherwise, the UE may increase CW_(p) forevery priority class p∈{1,2,3,4} to a next higher allowed value.

A reference subframe n_(ref) (or reference slot n_(ref)) is determinedin the following manner.

When the UE receives a UL grant in a subframe (or slot) n_(g) andtransmits a UL-SCH in subframes (or slots) n₀, n₁, . . . n_(w), startingfrom the subframe (or slot) no without a gap, the reference subframe (orslot) n_(ref) is the subframe (or slot) no.

(2) Type 2 UL CAP Method

When the UE uses the Type 2 CAP to transmit a UL signal (including thePUSCH) in a U-band, the UE may transmit the UL signal (including thePUSCH) in the U-band immediately after sensing that the channel is idleat least for a sensing period T_(short_ul) of 25 us. T_(short_ul)includes a duration T_(f) of 16 us immediately followed by one slotduration T_(sl) of 9 us. T_(f) includes an idle slot duration T_(sl) atthe start thereof.

Embodiment: HARQ-ACK Feedback in U-Band

To support standalone operation in a U-band, the UE may need to provideHARQ-ACK feedback for DL data (e.g., PDSCH) reception based onPUCCH/PUSCH transmission in the U-band (herein, HARQ-ACK is referred toas A/N). A PUCCH/PUSCH may mean a PUCCH or a PUSCH. For example, it maybe considered that the BS schedules DL data transmission to the UEwithin a channel occupancy time (COT) period, which is obtained by theLBT (CCA) operation, and instructs the UE to transmit A/N feedback forDL data reception within the same COT period (herein, CCA is referred toas LBT). In another example, it may be considered that due to a UEprocessing time required for decoding a DL data signal and encoding anA/N signal for the DL data signal, the BS instructs the UE to transmitA/N feedback for reception of DL data, which is scheduled/transmittedwithin a specific COT period, in another COT period behind thecorresponding COT period.

The present disclosure proposes a method of configuring/transmitting A/Nfeedback in a U-band. The A/N feedback configuration/transmission methodmay be performed in consideration of LBT operation, COT configurations,etc. The features of the present disclosure are not limited totransmission of A/N feedback over the PUCCH/PUSCH but applicable totransmission of other UCIs (e.g., CSI, SR, etc.) over the PUSCCH/PUSCHin a similar way. The features of the present disclosure are not limitedto LBT-based U-band operations but applicable to L-band (or U-band)operations with no LBT in a similar way. In the following, a pluralityof CCs (or CC indices) may be replaced with a plurality of BWPs (BWPindices) configured in one CC/(serving) cell (or multiple CCs/(serving)cells) or a plurality of CCs/(serving) cells including a plurality ofBWPs (i.e., a combination of CCs (CC indices) and BWPs (BWP indices)).

The terms used herein are defined as follows.

-   -   UCI: The UCI refers to control information transmitted from a UE        in UL. The UCI includes various types of control information        (UCI types). For example, the UCI may include a HARQ-ACK, an SR,        CSI, etc.    -   HARQ-ACK: The HARQ-ACK indicates whether DL data (e.g., a        transport block (TB), a codeword (CW), etc.) on the PDSCH is        successfully received. A 1-bit HARQ-ACK may be transmitted in        response to one piece of DL data, and a two-bit HARQ-ACK may be        transmitted in response to two pieces of DL data. HARQ-ACK        responses/results may include a positive ACK (ACK), negative ACK        (NACK), DTX, or NACK/DTX. Herein, HARQ-ACK is interchangeable        with ACK/NACK, A/N, or AN.    -   HARQ process number/ID: This represents the number or ID of a        HARQ process. The HARQ process manages state variables for the        number of times of MAC PDU transmission in a buffer, HARQ        feedback for a MAC PDU in a buffer, a current redundancy        version, etc.    -   PUCCH: The PUCCH refers to a physical layer uplink channel for        UCI transmission. In this document, PUCCH resources configured        and/or indicated by the BS to transmit an A/N, an SR, and CSI        are referred to as an A/N PUCCH resource, an SR PUCCH resource,        and a CSI PUCCH resource, respectively.    -   PUSCH: The PUSCH refers to a physical layer uplink channel for        UL data transmission.    -   Slot: The slot refers to a basic time unit (TU) (or time        interval) for data scheduling. The slot includes a plurality of        symbols. In this document, a symbol may be an OFDM-based symbol        (e.g., CP-OFDM symbol, DFT-s-OFDM symbol, etc.). Further, a        symbol is interchangeable with an OFDM-based symbol, OFDM        symbol, CP-OFDM symbol, and DFT-s-OFDM symbol.

Each of the following proposed methods may be applied together withother proposed methods unless they collide with each other.

(1) Basic Operation Modes

Hereinafter, basic operation modes for A/N feedbackconfiguration/transmission proposed in the present disclosure will bedescribed. In the present disclosure, A/N triggering DCI may at leastinclude DL grant DCI and further include UL grant DCI and/or specificDCI that does not schedule PDSCH/PUSCH transmission (in addition to theDL grant DCI).

1) Timing-based A/N feedback mode (t-A/N mode) (FIG. 12)

A. After preconfiguring a plurality of candidate HARQ timings throughRRC signaling, the BS may inform the UE of one of the candidate HARQtimings in (DL grant) DCI. The UE may transmit A/N feedback forreception of PDSCH(s) in a plurality of slots (or a set of slots), whichare related to a set of all candidate HARQ timings, at the indicatedHARQ timing (herein, a set of slots is referred to as a bundlingwindow). Here, the HARQ timing refers to a PDSCH-to-A/N timing/interval.The HARQ timing may be expressed in a unit of slot.

For example, if it is indicated that A/N transmission is performed inslot #m, A/N information may include a response for PDSCH reception inslot #(m-i), where slot #(m-i) corresponds to a candidate HARQ timing.FIG. 12(a) shows a case in which candidate HARQ timings are configuredas follows: i={2, 3, 4, 5}. If it is indicated that the A/N transmissiontime is slot #(n+5)(=m), the UE may generate/transmit A/N informationfor PDSCH reception in slots #n to #(n+3)(=m-i) (i.e., A/N feedback forall four slots). In this case, A/N responses for the PDSCH reception inslots #n+1 to #n+3 may be processed as NACK.

B. In addition to a HARQ timing indication, a counter downlinkassignment index (c-DAI) and/or a total-DAI (t-DAI) may also be includedin (DL grant) DCI. The counter-DAI may indicate how many PDSCHs arescheduled before a PDSCH related to the (DL grant) DCI. The total-DAImay indicate the total number of PDSCHs scheduled so far (until thecurrent slot) (or the total number of slots including the PDSCH). Inthis case, the UE may transmit A/N feedback for as many PDSCHs ascounter-DAI values from the initial counter-DAI value to the last(received) total-DAI value at the indicated HARQ timing. If the UE isconfigured with only one serving cell, the counter-DAI may have the samemeaning as the total-DAI. Thus, if there are a plurality of servingcells, the total-DAI may be included in the (DL grant) DCI. When the UEis configured with a plurality of serving cells, the counter-DAI may befirst calculated in the cell domain, and then indicate the schedulingorder of PDSCHs calculated in the time domain (or the order of servingcells (slots) including the PDSCH). Similarly, the total-DAI mayindicate the total number of PDSCHs scheduled so far (until the currentslot) (or the total number of serving cells (slots) including thePDSCH). The counter/total-DAI may be defined with respect to the PDCCH.In this case, the PDSCH may be replaced with the PDCCH, and a slotincluding the PDCCH may be replaced with a PDCCH monitoring occasionrelated to or including the PDCCH (or DCI).

To indicate the counter/total-DAI, two bits may be used. For numbersgreater than 4, the counter/total-DAI may be indicated as follows basedon modulo operation.

-   -   When the DAI bits are 00 (DAI value=1), 4n+1 is indicated (that        is, 1, 5, 9, . . . ).    -   When the DAI bits are 01(DAI value=2), 4n+2 is indicated (that        is, 2, 6, 10, . . . ).    -   When the DAI bits are 10 (DAI value=3), 4n+2 is indicated (that        is, 3, 7, 11, . . . ).    -   When the DAI bits are 11 (DAI value=4), 4n+4 is indicated (that        is, 4, 8, 12, . . . ).    -   where n is an integer greater than or equal to 0.

FIG. 12(b) illustrates a case in which the DAI is signaled in the (DLgrant) DCI in the same state as FIG. 12(a). Referring to FIG. 12(b), aPDSCH scheduled by DCI with DAI=00 may be received in slot #n, and aPDSCH scheduled by DCI with DAI=10 may be received in slot #(n+2). Inthis case, the UE may generate/transmit A/N information for reception ofonly three PDSCHs corresponding to consecutive DAI values (i.e.,DAI=00/01/11) (hereinafter, such consecutive DAI values are referred toas a DAI sequence). The A/N response for reception of a PDSCHcorresponding to DAI=01 may be processed as NACK.

2) Pooling-based A/N feedback mode (p-A/N mode) (FIG. 13)

A. The BS may instruct the UE to defer A/N feedback transmission forPDSCHs in DL grant DCI. Then, the BS may instruct the UE to transmit A/Nfeedback for PDSCHs related to (i) all DL HARQ process IDs or (2) somespecific DL HARQ process ID(s) in DCI (pooling). The A/N feedback may betransmitted at a timing configured/indicated by a specific signal (e.g.,RRC or DCI signaling). A/N pooling may be indicated by a DL grant (e.g.,DCI format 1_0/1_1), a UL grant (e.g., DCI format 0_0/0_1), or otherDCIs (e.g., UE (or UE-group) common DCI). For convenience ofdescription, DCI indicating A/N pooling is referred to as pooling DCI.HARQ process ID(s) to be pooled may be configured/defined in advance orindicated by the pooling DCI. The A/N pooling may be indicated for eachHARQ process ID, for a group of HARQ process IDs, or for all HARQprocess IDs.

For example, referring to FIG. 13, the UE may receive three PDSCHs fromthe BS. The HARQ process IDs (HpIDs) allocated to the PDSCHs may be 0,3, and 2. A/N pending for the three PDSCHs may be indicated by the DLgrant DCI (AN=pending). In this case, the UE defers A/N transmission forPDSCH reception corresponding to HpID=0/3/2. Thereafter, upon receivingthe pooling DCI (AN=pooling) from the BS, the UE may transmit A/N forPDSCH reception corresponding to all or some HPIDs at a time.

B. When counter/total-DAI signaling is configured in the t-A/N mode(e.g., when a DAI is signaled in DL grant DCI), the A/N pooling may bedefined as follow: A/N transmission for PDSCH(s) related to HARQ processID(s) (indicated by the pooling DCI) is pooled or A/N transmission forPDSCH(s) related to a total-DAI value (indicated by the pooling DCI) ispooled. In the latter case, the UE may transmit A/N information forreception of as many PDSCHs as the value from the initial counter-DAIvalue to the total-DAI value at a time.

(2) Proposed Method 1

According to proposed method 1, the A/N triggering DCI may include 1)timing-A indicating an actual A/N transmission timing and 2) a referenceA/N timing for a group of (DL PDSCH) slots for which A/N feedback isrequired.

Based on that, the UE may transmit A/N feedback for a related slot group(A/N feedback for PDSCH reception in the slot group) at the timeindicated by timing-A. In this case, A/N payloads may be mapped(ordered) in the order of slot indices in the corresponding slot group.

For example, the A/N triggering DCI may be transmitted/detected in/fromslot #n (if the A/N triggering DCI is the DL grant DCI, a related PDSCHmay be transmitted/detected in/from slot #n). In addition, thecorresponding DCI may indicate that timing-A=K and L. In this case, theUE may transmit A/N feedback for a slot group corresponding to slot#(n+K−L) (A/N feedback for PDSCH reception in the slot group) in slot#(n+K). A slot group may be defined as a timing set consisting ofmultiple (e.g., M) candidate timing values, D_m (m=0, 1, . . . , M−1).For example, a slot group corresponding to slot #n may be set/defined asM slots corresponding to slot #(n−D_m) or slot #(n+D_m) (m=0, 1, . . . ,M−1). In this case, the slot group corresponding to slot #(n+K−L) may beset/defined as slot #(n+K−L−D_m) or slot #(n+K−L+D_m) (m=0, 1, . . . ,M−1).

A timing set that defines a slot group may be equal to or different froma set of candidate timing-A values (e.g., K_m; m=0, 1, . . . , M−1),which may be indicated by timing-A. For example, a bundling windowcorresponding to slot #n includes slot #(n−K_m), and the slot groupcorresponding to slot #n may be defined by a timing set consisting ofK_m values (m=0, 1, . . . , M−1). For example, the A/N triggering DCImay be transmitted/detected in/from slot #n (if the A/N triggering DCIis the DL grant DCI, the related PDSCH may be transmitted/detectedin/from slot #n). In addition, the corresponding DCI may indicate thattiming-A=K and L. In this case, the UE may transmit A/N feedback for theslot group corresponding to slot #(n+K−L) (A/N feedback for PDSCHreception in the slot group) in slot #(n+K). The slot groupcorresponding to slot #(n+K−L) may be include slot #(n+K−(K_m+L)) (m=0,1, . . . , M−1).

When the A/N triggering DCI is equal to the DL grant DCI (that is, whenboth timing-A and timing-D are signaled in the DL grant DCI), the UE maycombine and transmit 1) A/N feedback for a bundling window related totiming-A (A/N feedback for PDSCH reception therein) and 2) A/N feedbackfor a slot group related to timing-D (A/N feedback for PDSCH receptiontherein) at the time indicated by timing-A (for example, the UE maysimultaneously transmit the A/N feedback for the bundling window and theA/N feedback for the slot group over one PUCCH/PUSCH).

For example, when the DL grant DCI or related PDSCH istransmitted/detected in/from slot #n and when the corresponding DCIindicates timing-A=K and timing-D=L, the UE may combine 1) A/N feedbackfor a bundling window corresponding to slot #(n+k) (A/N feedback forPDSCH reception therein) and 2) A/N feedback for a slot groupcorresponding to slot #(n+K−L) (A/N feedback for PDSCH receptiontherein) and then transmit the combined A/N feedback in slot #(n+K). Theslot group corresponding to slot #(n+K−L) may be set/defined as (i) slot#(n+K−L−D_m) or slot #(n+K−L+D_m) (m=0, 1, . . . , M−1) and/or (ii) slot#(n+K−(K_m+L)) (m=0, 1, . . . , M−1).

Additionally, it may be indicated by DCI that there is no timing-Dand/or no slot group related to timing-D (i.e., no A/N feedback requesttherefor) (for example, when the A/N triggering DCI is equal to the DLgrant DCI). For example, when timing-D is set to a specific value (e.g.,0), it may be indicated that there is no slot group relate to timing-D(i.e., no A/N feedback request therefor).

Additionally, it may be indicated by DCI (for example, by a timing-Dindication field) that A/N feedback is required only for specific slots(e.g., first or last slot) among slots included in the bundling windowrelated to timing-A (or the slot group related to timing-D) (forexample, when the A/N triggering DCI is equal to the DL grant DCI).

As another method, it may be also considered that timing-A/timing-Dand/or A/N feedback transmission triggering for the slot group (orbundling window) related to timing-A/timing-D are signaled by UE (orUE-group) common DCI.

The reference A/N timing indicated by timing-D (a slot group for whichA/N feedback is required) may be restricted due to limitations on thesize (the number of bits) of a DCI field. In consideration of therestriction, it may be indicated by a specific state of the timing-Dindication field that A/N feedback is required for reception of PDSCHsrelated to all HARQ process IDs or some (predetermined) specific HARQprocess IDs (rather than a specific slot group).

A different A/N transmission PUCCH/PUSCH resource (set) may beconfigured for each value of timing-D. For example, a different A/Ntransmission PUCCH/PUSCH resource (set) may be configured for each slotgroup related to each timing-D value. Alternatively, the value oftiming-D (related to a slot group for which A/N feedback is required ona corresponding PUCCH/PUSCH resource (set)) may vary for each A/Ntransmission PUCCH/PUSCH resource (set).

(3) Proposed Method 2

According to proposed method 2, when the size of one slot group ispredetermined (for example, when the number of slots in one slot group Nor the maximum number of PDSCHs scheduled in one slot group N ispredetermined), 1) a current-ID (c-ID) indicating the ID of a slot groupincluding a slot in which DL grant DCI or a PDSCH corresponding the DLgrant DCI is transmitted may be signaled by the corresponding DCI,and/or 2) a feedback-ID (f-ID) indicating the ID of a (DL PDSCH) slotgroup for which A/N feedback is required may be signaled by A/Ntriggering DCI.

In this case, the UE may transmit A/N feedback for a slot group relatedto the feedback-ID (A/N feedback for PDSCH reception therein) at anindicated A/N transmission timing (e.g., a slot). The slot group relatedto the feedback-ID may include a slot in which a current-ID having thesame value as the f-I D has been signaled/received, that is, a slot inwhich the current-ID having the same value as the feedback-ID has beensignaled/received in the DL grant DCI.

In this case, A/N payloads may be mapped (ordered) in the order ofcounter-DAI values (e.g., from 1 to N) received in the DL grant DCI forthe slot group related to the feedback-ID (when the counter-DAI issignaled in the DL grant DCI).

For example, referring to FIG. 14, the A/N triggering DCI may betransmitted/detected in/from slot #n (if the A/N triggering DCI is theDL grant DCI, a related PDSCH may be transmitted/detected in/from slot#n). In addition, the corresponding DCI may indicate that timing-A(T-A)=K and feedback-ID (f-ID)=X. In this case, the UE may transmit A/Nfeedback for PDSCH reception in a slot group corresponding to slot groupID=X (where the DL grant DCI indicates current-ID=X) in slot #(n+K).

As shown in FIG. 12(b), it may be determined/signaled that thecounter-DAI has consecutive values (starting from the initial value(e.g., 1)) in one slot group (ID). The counter-DAI value may bedetermined/signaled independently for different slot groups. Inaddition, a slot group may be defined in the form of a DAI sequenceconsisting of counter-DAI values from 1 to N, which are related to thesame slot group ID value (indicated by DCI). In this case, the slotgroup may include non-consecutive slots based on the received/detectedcounter-DAI. In this document, a slot group ID may bereplaced/substituted with a DAI sequence ID.

When the A/N triggering DCI is equal to the DL grant DCI (that is, whenboth the current-ID and feedback-ID are signaled in the DL grant DCI),the UE may combine (concatenate) and transmit 1) A/N feedback for abundling window related to timing-A or a slot group related to thecurrent-ID (A/N feedback for PDSCH reception therein) and 2) A/Nfeedback for a slot group related to the feedback-ID (A/N feedback forPDSCH reception therein) at the time indicated by timing-A (at the sametime, for example over one PUCCH/PUSCH).

When it is said in this document that the feedback-ID is signaled by theA/N triggering DCI (e.g., DL grant DCI, UL grant DCI, etc.), it may meanthat the corresponding DCI includes a total-ID indicating the totalnumber of (PDSCH) slot groups (IDs) for which A/N feedback is requiredand a specific slot group ID determined by the total-ID and current-IDis applied as the feedback-ID. For example, when a maximum of two(PDSCH) slot group IDs (e.g., ID=0 or ID=1) are configured, if it isindicated that current-ID=X and total-ID=1, the feedback-ID may bedetermined/applied as X (which is the same as the current-ID). Inanother example, when a maximum of two (PDSCH) slot group IDs (e.g.,ID=0 or ID=1) are configured, if it is indicated that current-ID=X andtotal-ID=2, the feedback-ID may be determined/applied as Y (which isdifferent from the current-ID). X and Y may be different from each other(for example, Y=1 if X=0, or Y=0 if X=1). The method of determining afeedback-ID is referred to as “Method 1” for convenience.

For example, the DL grant DCI or related PDSCH may betransmitted/detected in/from slot #n, and the corresponding DCI mayindicate timing-A=K, current-ID=X, and feedback-ID=Y (or total-ID=2). Inthis case, the UE may combine 1) A/N feedback for a bundling windowcorresponding to slot #(n+k) or a slot group corresponding to ID=X (A/Nfeedback for PDSCH reception therein) and 2) A/N feedback for a slotgroup corresponding to ID=Y (A/N feedback for PDSCH reception therein)and then transmit the combined A/N feedback in slot #(n+K).

In this document, a total-DAI and/or new feedback indicator (NFI) forthe feedback-ID (or a (PDSCH) slot group related thereto)signaled/indicated by the A/N triggering DCI (e.g., DL grant DCI, ULgrant DCI, etc.) may mean a total-DAI and/or NFI for a feedback-IDdetermined according to Method 1 or a total-DAI and/or NFI for another-ID (or a slot group related thereto) which is different from thecurrent-ID (regardless of the value indicated by the total-ID). As anexample for the latter, when a maximum of two (PDSCH) slot group IDs(e.g., ID=0 or ID=1) are configured, if it is indicated thatcurrent-ID=X, the total-DAI and/or NFI for the feedback-ID may mean atotal-DAI and/or NFI for a slot group related to other-ID=Y. X and Y maybe different from each other (for example, Y=1 if X=0, or Y=0 if X=1).The method of determining an other-ID and applying a total-DAI/NFI isreferred to as “Method 2” for convenience.

The NFI may be 1-bit information and indicate whether the BS (a)successfully receives/detects previously (or recently) transmitted A/Nfeedback (such A/N feedback is referred as previous A/N feedback) or (b)fails in the reception/detection. In the case of (a), the UE mayconfigure/transmit updated A/N feedback by processing a remaining partexcept A/N for PDSCH(s) scheduled after the previous A/N transmission asNACK or DTX (or by dropping the feedback configuration/transmission). Inthe case of (b), the UE may configure/transmit A/N feedback bymaintaining the remaining part except the A/N for the PDSCH(s) scheduledafter the previous A/N transmission. In the case of (a), an NFI valuetoggled from an NFI value received in previous DCI may be indicated bycurrent DCI. In the case of (b), an NFI value non-toggled from the NFIvalue received by the previous DCI may be indicated by the current DCI.

Additionally, it may be indicated by DCI (for example, by a feedback-ID(or total-ID) indication field) that there is no feedback-ID (or noother-ID) and/or no slot group related thereto (i.e., no A/N feedbackrequest therefor) (for example, when the A/N triggering DCI is equal tothe DL grant DCI). For example, when it is indicated that thefeedback-ID is equal to the current-ID (or when the total-ID is 1), theUE may configure/transmit A/N feedback for slot group(s) related to thecurrent-ID.

Additionally, it may be indicated by DCI (for example, by thefeedback-ID (or total-ID) indication field) that A/N feedback isrequired only for specific slots (e.g., first or last slot) among slotsincluded in the bundling window related to timing-A or slot grouprelated to the current-ID (or slot group related to the feedback-ID (orother-ID)) (for example, when the A/N triggering DCI is equal to the DLgrant DCI).

As another method, it may be also considered that the current-ID issignaled by UE (or UE-group) common DCI #1 and/or the feedback-ID andA/N feedback transmission triggering for the slot group related to thefeedback-ID is signaled by UE (or UE-group) common DCI #2. In this case,UE (or UE-group) common DCI #land UE (or UE-group) common DCI #2 may bedifferent from each other or integrated as one DCI.

As another method, when the total-DAI is signaled by the A/N triggeringDCI, the UE may configure/transmit A/N feedback only for the value(s) ofthe counter-DAI (from 1) to the value of the total-DAI for the slotgroup related to the feedback-ID (the bundling window related totiming-A or the slot group related to the current-ID). That is, the UEmay configure/transmit A/N feedback only for slot(s) related to thecounter-DAI value(s) from 1 to the total-DAI value (or PDSCHs scheduledthereby). Alternatively, the total-DAI may be separately signaled by DCIfor each of the following: the slot group related to the feedback-ID (orother-ID) and the slot group related to the current-ID (or bundlingwindow related to timing-A). In this case, the UE may configure A/Nfeedback based on the total-DAI for each slot group.

For example, information about an A/N feedback configuration, which isindicated by the DL grant DCI, may at least include (i) the current-ID,(ii) the counter/total-DAI for the slot group (or PDSCHs scheduled inthe slot group) related to the current-ID, and (iii) the feedback-ID (ortotal-ID). The total-DAI for the slot group (or PDSCHs scheduled in theslot group) related to the feedback-ID (or other-ID) may be furtherincluded in the DL grant DCI (i.e., A/N feedback configuration relatedinformation).

The UL grant DCI may indicate (i) the current-ID, (ii) the total-DAI forthe slot group (or PDSCHs scheduled in the slot group) related to thecurrent-ID, (iii) the feedback-ID (or total-ID), and (iv) the total-DAIfor the slot group related to the feedback-ID (or other-ID). In thiscase, the current-ID and feedback-ID may be defined/generalized as twofeedback-IDs: feedback-IDs #1 and #2. Accordingly, the UE may transmitA/N feedback for slot groups related to feedback-IDs #1 and #2 over thePUSCH (or PUCCH) (for example, in the form of UCI piggyback).

As another method, the UL grant DCI may not include the current-ID(and/or feedback-ID (or total-ID)). That is, signaling of the current-ID(and/or feedback-ID (or total-ID)) in the UL grant DCI may be dropped.In this case, the UE may configure/transmit A/N feedback (on the PUSCH)based on information about the current-ID (and/or feedback-ID (ortotal-ID)) received by the DL grant DCI. Additionally, it may beindicated by a specific field in the UL grant DCI that there is no A/Nfeedback transmission request (e.g., there is no slot group for whichA/N feedback is required). The specific field may include thefeedback-ID (or total-ID) indication field and/or a current-ID (and/orfeedback-ID (or other-ID) and/or total-DAI related to current-ID)indication field.

As another method, the current-ID and a starting-ID may be indicated bythe A/N triggering DCI (e.g., DL grant DCI, UL grant DCI, etc.). In thiscase, the UE may be configure/transmit A/N feedback for slot group set Arelated to (a plurality of) consecutive slot group ID(s) from thestarting-ID to the current-ID (A/N feedback for PDSCH receptiontherein). When it is indicated that the starting-ID is equal to thecurrent-ID, the UE may configure/transmit A/N feedback for only slotgroup(s) related to the current-ID. The current-ID may bedefined/generalized as an ending-ID.

For example, the A/N feedback configuration related informationindicated by the DL grant DCI may at least include (i) the current-ID,(ii) the counter/total-DAI for the slot group (or PDSCHs scheduled inthe slot group) related to the current-ID, and (iii) the starting-ID.The DL grant DCI (i.e., A/N feedback configuration related information)may further include total-DAI(s) commonly applied to each of (aplurality of) slot group(s) included in slot group set A (except theslot group related to the current-ID).

In another example, the UL grant DCI may indicate (i) the current-ID,(ii) the total-DAI for the slot group related to the current-ID (PDSCHsscheduled thereby), (iii) the starting-ID, and (iv) the total-DAI(s)commonly applied to each of (the plurality of) the slot group(s)included in slot group set A (except the slot group related to thecurrent-ID). Accordingly, the UE may transmit A/N feedback for a slotgroup set from the starting-ID to the current-ID over the PUSCH (orPUCCH) (in the form of UCI piggyback).

In another example, the UL grant DCI may not include the current-ID(and/or starting-ID). That is, signaling of the current-ID (and/orstarting-ID) in the UL grant DCI may be dropped. In this case, the UEmay configure/transmit A/N feedback (on the PUSCH) based on informationabout the current-ID (and/or starting-ID) received by the DL grant DCI.Additionally, it may be indicated by a specific field in the UL grantDCI that there is no A/N feedback transmission request (e.g., there isno slot group for which A/N feedback is required). The specific fieldmay include a starting-ID indication field and/or a current-ID (and/orrelated total-DAI) indication field.

When the above-described method or other different methods are applied,the number of slot groups for which (one-shot) simultaneous A/N feedbackis required may be dynamically changed (for example, there may be two,three, or more slot groups including the current-ID). In this case, theA/N triggering DCI (e.g., DL grant DCI) and/or UL grant DCI may indicatetotal-DAI(s) commonly applied to a plurality of slot groups for whichA/N feedback is required (except the slot group related to thecurrent-ID).

Slot group IDs indicated by the current-ID/feedback-ID (or total-ID)(slot groups for which A/N feedback is required) may be restricted dueto limitations on the size (the number of bits) of a DCI field. Inconsideration of the restriction, it may be indicated by a specificstate of a current-ID/feedback-ID (or total-ID) indication field thatA/N feedback is required for reception of PDSCHs related to all HARQprocess IDs or some (predetermined) specific HARQ process IDs (ratherthan a specific slot group).

A different A/N transmission PUCCH/PUSCH resource (set) may beconfigured for each slot group ID value (or for each slot group relatedto the ID). Alternatively, the slot group ID value (for which A/Nfeedback is required on a corresponding PUCCH/PUSCH resource (set)) mayvary for each A/N transmission PUCCH/PUSCH resource (set). For example,the UE may transmit A/N feedback for slot group ID=X by selecting/usinga PUCCH/PUSCH resource (set) configured for slot group ID=X.

Additionally, when a plurality of carriers are aggregated/configured forone UE (i.e., in the CA environment), the same slot group ID may becommonly indicated/defined for all the plurality of carriers at the sametiming (slot timing) or within the same time period (Opt 1-1), or a slotgroup ID may be indicated/defined for each of the plurality of carriersin a frequency-first and time-second manner (in a carrier-first andslot-group-second manner) (Opt 1-2).

Additionally, when slot group IDs are indicated/defined in the CAenvironment, the counter-DAI may be determined/indicated as follows: 1)a PDSCH scheduling counter value may be determined/indicated within oneslot group (ID) in a frequency-first (carrier-first) and time-second(slot-second) manner (when Opt 1-1 is applied); or 2) a PDSCH schedulingcounter value may be determined/indicated independently for each carrierwithin one slot group (ID) (when Opt 1-2 is applied).

FIG. 15 illustrates an A/N transmission process according to an exampleof the present disclosure. Referring to FIG. 15, a UE may receive firstDCI including a counter-DAI and slot group indication information(S1502). The counter-DAI may indicate a scheduling order in a slotgroup, and the slot group indication information may indicate a firstslot group among a plurality of slot groups. The UE may receive DL databased on the first DCI (S1504). Thereafter, the UE may receive secondDCI including a total-DAI and requesting A/N feedback for the first slotgroup among the plurality of slot groups (S1506). The total-DAIindicates the total number of times that scheduling is performed in aslot group. The UE may transmit UCI including A/N information for thefirst slot group based on the counter-DAI and the total-DAI (S1508). Thesize of the A/N information for the first slot group may be determinedbased on the total-DAI, and A/N information may be arranged in the orderof values of the counter-DAI in the A/N information for the first slotgroup. The UCI may be transmitted in a U-band (e.g., UCell).

The second DCI may include DCI may include DCI scheduling a PDSCH, andthe second DCI may include first information about the index of a slotgroup including the PDSCH and second information indicating that thefirst slot group is a slot group for which A/N feedback is required. Theslot group indicated by the first information may be different from thefirst slot group. The second DCI may further include a total-DAI for theslot group including the PDSCH.

(4) Proposals

Before describing the proposed methods, the A/N feedbackconfiguration/transmission and basic operation modes therefor will bedescribed in brief. The t-A/N and p-A/N modes are substantially the sameas those described above with reference to FIGS. 12 and 13, but themodes are summarized again to classify A/N feedbackconfiguration/transmission modes (or A/N codebook modes).

1) Timing-based A/N feedback mode (t-A/N mode)

A. After configuring a plurality of candidate HARQ timings through RRCsignaling, the BS may inform the UE of one of the candidate HARQ timingsin (DL grant) DCI. The UE may transmit A/N feedback for reception ofPDSCH(s) in a plurality of slots (or a set of slots), which are relatedto a set of all candidate HARQ timings, at the indicated HARQ timing(herein, a set of slots is referred to as a bundling window). Here, theHARQ timing refers to a PDSCH-to-A/N timing/interval. The HARQ timingmay be expressed in a unit of slot. The above-described mode is referredto as a Type-1 A/N codebook.

B. In addition to a HARQ timing indication, a counter-DAI and/or atotal-DAI may also be included in (DL grant) DCI. The counter-DAI mayindicate how many PDSCHs are scheduled before a PDSCH related to the (DLgrant) DCI. The total-DAI may indicate the total number of PDSCHsscheduled so far (until the current slot) (or the total number of slotsincluding the PDSCH). In this case, the UE may transmit A/N for as manyPDSCHs as counter-DAI values from the initial counter-DAI value to thelast (received) total-DAI value at the indicated HARQ timing. Theabove-described mode is referred to as a Type-2 A/N codebook.

C. A/N feedback mode based on PDSCH (slot) group IDs (Type-2a A/Ncodebook)

i. A current-ID may be signaled in DL grant DCI, and a feedback-ID maybe signaled in A/N triggering DCI. The current-ID is used to indicatethe ID of a slot group including a slot in which the DL grant DCI or aPDSCH related thereto is transmitted. The feedback-ID is used toindicate the ID of a (DL PDSCH) slot group for which A/N feedback isrequired. In this case, a total-ID may be signaled by the DCI, and thefeedback-ID may be obtained from the total-ID according to Method 1.

ii. The UE may transmit A/N feedback for a slot group related to thefeedback-ID (A/N feedback for PDSCH reception therein) at an indicatedA/N transmission timing.

iii. When the A/N triggering DCI is equal to the DL grant DCI (that is,when both the current-ID and feedback-ID (or total-ID) are signaled inthe DL grant DCI), the UE may combine and transmit 1) A/N feedback for abundling window related to timing-A or a slot group related to thecurrent-ID (A/N feedback for PDSCH reception therein) and 2) A/Nfeedback for the slot group related to the feedback-ID (A/N feedback forPDSCH reception therein) at the time indicated by timing-A (at the sametime, for example over one PUCCH/PUSCH).

2) Pooling-based A/N feedback mode (p-A/N mode)

A. The BS may instruct the UE to defer A/N feedback transmission forPDSCHs in DL grant DCI. Then, the BS may instruct the UE to transmit A/Nfeedback for PDSCHs related to (i) all DL HARQ process IDs or (ii) somespecific DL HARQ process ID(s) in DCI (pooling). The A/N feedback may betransmitted at a timing configured/indicated by a specific signal (e.g.,RRC or DCI signaling). The above-described mode is referred to as aType-3 A/N codebook.

B. When counter/total-DAI signaling is configured in the t-A/N mode(e.g., when a DAI is signaled in DL grant DCI), the A/N pooling may bedefined as follow: A/N transmission for PDSCH(s) related to HARQ processID(s) (indicated by pooling DCI) is pooled or A/N transmission forPDSCH(s) related to a total-DAI value (indicated by the pooling DCI) ispooled. In the latter case, the UE may transmit A/N information forreception of as many PDSCHs as the value from the initial counter-DAIvalue to the total-DAI value at a time.

3) Dynamic switching between the t-A/N and p-A/N modes

A. For example, DL grant DCI may indicate switching between the t-A/Nand p-A/N modes. That is, the DL grant DCI may indicate which one of thet-A/N and p-A/N modes is used to configure/transmit A/N feedback.Additionally, both A/N pending and A/N pooling for the p-A/N mode mayalso be indicated by the same DL grant DCI. For example, when DL grantDCI indicates the p-A/N mode, the corresponding DL grant DCI may furtherindicate whether A/N feedback is pending or pooled.

B. In another example, DL grant DCI may indicate switching between A/Npending operations to apply the t-A/N or p-A/N mode. That is, the DLgrant DCI may indicate whether to apply the t-A/N mode or to defer A/Nfeedback transmission for the p-A/N mode. In this case, the A/N poolingoperation for the p-A/N mode may be indicated in UL grant DCI or (UE orUE-group) common DCI.

C. As a further example, DL grant DCI including PDSCH scheduling mayindicate switching between the t-A/N mode and A/N pending for p-A/N.That is, the DL grant DCI may indicate whether to apply the t-A/N modeor defer A/N transmission for the p-A/N mode. In this case, A/N poolingfor the p-A/N mode may be indicated by DL grant DCI including no PDSCHscheduling.

4) NFI information signaling

A. To prevent inconsistency between the A/N codebook (payload)configurations of the UE and BS, which results from when the UE dropsA/N feedback transmission due to LBT failure and/or when the BS fails todetect A/N feedback (and update a contention window size (CWS) for LBToperation required for UL transmission including an A/N PUCCH, a PUSCH,etc.), a 1-bit NFI may be signaled in DCI triggering A/N feedbacktransmission (e.g., DL grant DCI or UL grant DCI). The NFI may betoggled to indicate the following information.

i. The NFI may indicate whether the BS (a) successfully receives/detectspreviously (or recently) transmitted A/N feedback (such A/N feedback isreferred as previous A/N feedback) or (b) fails in thereception/detection. In the case of (a), the UE may configure/transmitupdated A/N feedback by processing a remaining part except A/N forPDSCH(s) scheduled after the previous A/N transmission as NACK or DTX(or by dropping the feedback configuration/transmission). In the case of(b), the UE may configure/transmit A/N feedback by maintaining theremaining part except the A/N for the PDSCH(s) scheduled after theprevious A/N transmission.

ii. In the case of (a), an NFI value toggled from an NFI value receivedin previous DCI may be indicated by current DCI. In the case of (b), anNFI value non-toggled from the NFI value received by the previous DCImay be indicated by the current DCI. Upon receiving the toggled NFI, theUE may reset the CWS for A/N PUCCH (and/or PUSCH) transmission to theminimum. On the contrary, upon receiving the non-toggled NFI, the UE mayincrease the CWS (by a predetermined amount).

Hereinafter, a description will be given of a method of configuringDL/UL grant DCI and signaling information when the Type-2a and Type-1A/N codebooks are configured. In this document, DCI (format) where DCIformat fields and field sizes are configurable (variable) is referred toas non-fallback DCI, and DCI (format) where DCI format fields and fieldsizes are non-configurable (fixed) is referred to as non-fallback DCI.Herein, DCI may mean non-fallback DCI unless specified as fallback DCI.

(a) DCI Configuration and Signaling Information in Configuration ofType-2a A/N Codebook

1) Information signaled in DL grant DCI

A. Basically, the following information may be included (basicinformation).

i. Information about a current-ID

ii. Information about a counter-DAI and a total-DAI for a (PDSCH) slotgroup related to the current-ID

iii. Information about a feedback-ID

1. Alternatively, a total-ID may be signaled by DCI, and the feedback-IDinformation may be determined according to Method 1.

iv. Information about an NFI related to A/N feedback for the current ID(i.e., NFI for current-ID)

v. Information about an NFI related to A/N feedback for the feedback-ID(i.e., NFI for feedback ID)

1. Information about an NFI related to A/N feedback for an other-IDhaving a different value from the current-ID (regardless of the valueindicated by the total-ID) (i.e., NFI for other-ID) may be usedaccording to Method 2.

B. Additionally, the following information may be further included.

i. Information about a total-DAI for a (PDSCH) slot group related to thefeedback-ID

1. Information about a total-DAI related to A/N feedback for theother-ID having a different value from the current-ID (regardless of thevalue indicated by the total-ID) (i.e., total-DAI for other-ID) may beused according to Method 2.

C. Additionally, the following information may be further included.

i. Information on whether A/N feedback is configured/transmitted basedon the Type-3 codebook (e.g., a codebook type indicator (CTI) indicatingwhich one of the Type-2a and Type-3 A/N codebooks is used)

ii. Notes

1. If Type-3 is indicated by DCI (at a specific time), information aboutan NFI related to A/N feedback based on the Type-3 codebook (i.e., NFIfor Type-3) may be additionally signaled by the corresponding DCI.

2. The CTI information may be explicitly signaled by one dedicated bitor implicitly signaled as follows.

3. In a first method, when it is indicated by the DCI that A/N feedbacktransmission is required only for one (PDSCH) slot group related to thecurrent-ID, the CTI information may be signaled by an NFI forfeedback-ID (or NFI for other-ID) bit/field. When the CTI indicatesType-3, a HARQ process ID group and/or a cc/cell group (in the CAenvironment) for which A/N feedback is required may be indicated by acounter-DAI bit/field, a total-DAI bit/field, and/or an NFI forcurrent-ID bit/field, and/or information about the NFI for Type-3 may besignaled.

4. In a second method, when it is indicated by DCI that A/N feedbacktransmission is required only for one (PDSCH) slot group related to thecurrent-ID, the CTI information may be signaled by a total-DAI forfeedback-ID (or total-DAI for other-ID) bit/field. When the CTIindicates Type-3, a HARQ process ID group and/or a cc/cell group (in theCA environment) for which A/N feedback is required may be indicated by acounter-DAI bit/field, a total-DAI (for current-ID) bit/field, an NFIfor current-ID bit/field, and/or an NFI for feedback-ID (or NFI forother-ID) bit/field, and/or information about the NFI for Type-3 may besignaled.

D. DL scheduling based on fallback DCI

i. Basically, fallback DCI formats may include/signal only thecurrent-ID information and counter-DAI information (for the (PDSCH) slotgroup related to the corresponding ID) among the basic information (sucha case is referred to as Case 1).

ii. Alternatively, the fallback DCI format may include/signal all basicinformation except a total-DAI for current-ID.

iii. In this case, for information that is not included/signaled by thefallback DCI, the UE may configure/transmit an A/N codebook (payload)based on the most recently detected/received information fromnon-fallback DL DCI (e.g., feedback-ID (or total-ID), NFI, CTI, etc.).The non-fallback DL DCI related to the recently detected/receivedinformation may be limited only to DCI indicating the same HARQ-ACK(PUCCH) transmission time as a HARQ-ACK (PUCCH) transmission time (orslot) indicated by the fallback DL DCI. If there is no non-fallback DCIindicating the same HARQ-ACK (PUCCH) transmission time as the fallbackDCI, the UE may configure/transmit A/N feedback only for the slot grouprelated to the current-ID as in Case 1. In addition, the UE mayassume/apply toggling (or non-toggling) for the NFI for current-ID(compared to the previous A/N feedback or previously (recently) receivedNFI bit). Further, the UE may operate by assuming that the Type-2acodebook is indicated by the CTI.

E. DL transmission operation on CBG basis

i. For a CC/cell where DL transmission is configured on a CBG basis, anA/N sub-codebook where information about the total-DAI for feedback-ID(or total-DAI for other-ID) is transmitted for each TB and an A/Nsub-codebook where the information is transmitted for each CBG may beseparately signaled.

2) Information signaled in UL grant DCI

A. Basically, the following information may be included (basicinformation).

i. Information about a total-DAI for a first (PDSCH) slot group ID(first-ID)

ii. Information about a total-DAI for a second (PDSCH) slot group ID(second-ID)

iii. Notes

1. For example, when a maximum of two (PDSCH) slot groups (indices=0and 1) are defined/configured, the first-ID and second-ID may correspondto slot group indices 0 and 1, respectively.

2. In another example, the current-ID and feedback-ID (or other-ID) maybe set/replaced to/with the first-ID and the second-ID, respectively. Inthis case, information about the current-ID and information about thefeedback-ID (or total-ID) may be further signaled by DCI.

A. DCI may include the total-ID rather than the feedback-ID, and thefeedback-ID information may be determined according to Method 1.

B. A slot group ID having a different value from the current-ID may bedetermined as the other-ID according to Method 2.

3. As a further example, bitmap information about a set of all slotgroup IDs/indices (e.g., IDs/indices=0 and 1) may be signaled by DCI.Whether A/N feedback is required for a slot group corresponding to eachID may be indicated for each slot group ID by the corresponding bitmap.

4. The UL grant DCI may include no slot group ID/index-relatedinformation/signaling. In this case, the UE may configure/transmit anA/N codebook (payload) based on the most recently detected/received slotgroup ID/index information from the DL grant DCI. The DL grant DCIrelated to slot group IDs/indices may be limited only to DCI indicatingthe same PDSCH HARQ-ACK transmission time as a PUSCH transmission time(slot) scheduled by the UL grant DCI.

B. Additionally, the following information may be further included.

i. Information about an NFI related to A/N feedback related to thefirst-ID

ii. Information about an NFI related to A/N feedback related to thesecond-ID

iii. Notes

1. In this case, even if there is no additional DL (PDSCH)scheduling/transmission from the BS, the UE may be configured with A/Nfeedback transmission (over the PUSCH).

2. Otherwise, the UL grant DCI may include no NFI information about A/Nfeedback. In this case, the UE may configure/transmit an A/N codebook(payload) based on the most recently detected/received NFI informationfrom the DL grant DCI (for each (PDSCH) slot group). The DL grant DCIrelated to the NFI information may be limited only to DCI indicating thesame PDSCH HARQ-ACK transmission time as a PUSCH transmission time(slot) scheduled by the UL grant DCI.

C. Additionally, the following information may be further included.

i. Information on whether A/N feedback is configured/transmitted basedon the Type-3 codebook (e.g., information on which one of the Type-2aand Type-3 A/N codebooks is used)

ii. Notes

1. If Type-3 is indicated by DCI (at a specific time), the informationabout an NFI related to A/N feedback based on the Type-3 codebook may beadditionally signaled by the corresponding DCI.

D. UL scheduling based on fallback DCI

i. Basically, fallback DCI formats may not include/signal all basicinformation (all basic information may be dropped).

ii. Alternatively, the fallback DCI formats may include/signal all basicinformation.

iii. In this case, for information that is not included/signaled by theUL grant DCI, the UE may configure/transmit an A/N codebook (payload)based on the most recently detected/received information from the DLgrant DCI (e.g., slot group ID/index, NFI, CTI, etc.) In this case, theDL grant DCI related to the recently detected/received information maybe limited only to DCI indicating the same PDSCH HARQ-ACK transmissiontime as a PUSCH transmission time (or slot) scheduled by the UL grantDCI.

iv. When A/N is piggybacked on a configured grant PUSCH (CG-PUSCH),which is transmitted in the form of a CG without DCI, instead ofscheduling with dynamic grant DCI transmission, the UE mayconfigure/transmit an A/N codebook (payload) based on the most recentlydetected/received information from the DL grant DCI (e.g., slot groupID/index, total-DAI, NFI, CTI, etc.). The DL grant DCI related to therecently detected/received information may be limited only to DCIindicating the same PDSCH HARQ-ACK transmission time as a CG-PUSCHtransmission time (slot).

E. DL transmission operation on CBG basis

i. For a CC/cell where DL transmission is configured on a CBG basis, anA/N sub-codebook where information about the total-DAI (e.g., total-DAIfor first-ID and total-DAI for second-ID) is transmitted for each TB andan A/N sub-codebook where the information is transmitted for each CBGmay be separately signaled.

When the UE configures/transmits A/N feedback over the PUCCH/PUSCH basedon Type-2a codebook, the BS may need to notify/inform the UE that no A/Nfeedback is piggybacked on the PUSCH. To this end, the following DCIsignaling and operations may be considered.

1) Method 1

A. The UE may not perform A/N piggyback on the PUSCH in the followingcase: when total-DAI bits in the UL grant DCI are set to ‘11’ (or whenthe total-DAI value is set to 4); when no DL grant DCI is detectedwithin a bundling window related to a PUSCH transmission time (or a timeperiod from a previous (recent) A/N feedback transmission time (or anindicated transmission time) to the PUSCH transmission time; and whenthe NFI bit indicated by the UL grant DCI is toggled (compared to theprevious A/N feedback or previously (recently) received NFI bit). Thismethod may be applied when NFI information is signaled by the UL grantDCI. In this case, the DCI checking and UE operations therefor may beperformed independently/separately for each (PDSCH) slot group (ID).

B. As another method, the UE may apply/perform the DCI checking/UEoperations to/for the detected/received UL grant DCI (when no NFIinformation is signaled by the UL grant DCI), and the UE may assume thatthe NFI bit is non-toggled (or toggled) (compared to the previous A/Nfeedback or previously (recently) received NFI bit). This method may beapplied when the UL grant DCI (format) has no NFI information signaling(e.g., fallback UL grant DCI).

2) Method 2

A. One of the states signaled by a total-DAI field in the UL grant DCImay be defined such that it indicates that there is no A/N feedback(piggybacked on the PUSCH). When the corresponding state is indicated bythe DCI, the UE may not perform A/N piggyback on the PUSCH. This methodmay be applied when no NFI information is signaled by the UL grant DCI.In this case, the DCI checking and UE operations therefor may beperformed independently/separately for each (PDSCH) slot group (ID).

3) Method 3

A. Only one (PDSCH) slot group (e.g., first-ID) may be indicated byfirst-ID and second-ID (or current-ID and feedback-ID (or total-ID))bits/fields in the UL grant DCI. In this case, a specific total-DAIfield (e.g., total-DAI field for second-ID) may indicate: 1) A/Nfeedback for the indicated one slot group (e.g., first-ID) needs to beconfigured/transmitted (through piggyback on the PUSCH); or 2) there isno A/N feedback piggybacked on the PUSCH even for the indicated one slotgroup (e.g., first-ID) (that is, for all slot groups (first ID andsecond-ID)). This method may be applied when (PDSCH) slot group IDinformation is signaled by the UL grant DCI (and no NFI information issignaled by the UL grant DCI). For example, the slot group IDinformation may include information about the first-ID and second-ID (orinformation about the current-ID and feedback-ID (or total-ID)).

When a plurality of PUSCH resources transmitted in multiple slots arescheduled/indicated by one piece of UL grant DCI (i.e., multi-slotscheduling), how to apply total-DAI, NFI, and/or CTI informationsignaled by the corresponding DCI may need to be considered. Thecorresponding information may be applied to 1) (a) a PUSCH resource inthe first slot (i.e., first-slot PUSCH), (b) a first PUSCH resource(i.e., first PUSCH), (c) a first PUSCH resource including a specificnumber or more of symbols (or non-DMRS symbols) and/or a specific numberor more of RBs (REs or non-DMRS REs), (d) a PUSCH resource allocated toa slot immediately after a first slot for PUSCH transmission, or (e) afirst PUSCH resource having the same symbol duration as a slot duration(i.e., first-full PUSCH) among a plurality of slots or PUSCH resourcesscheduled by DCI (for example, the information may be applied to aspecific one of the plurality of resources or a specific resourcecombination thereof); 2) (a) a first slot PUSCH where initial LBT (orCCA) is successful, (b) the first PUSCH, or (c) the first full-PUSCH; or3) (a) a first-slot PUSCH where A/N feedback is transmitted throughpiggyback, (b) the first PUSCH, or (c) the first full-PUSCH. For theremaining slots or PUSCH resources except the above slots or PUSCHresources, a) an A/N codebook (payload) may be configured/transmittedbased on the most recently detected/received information from the DLgrant DCI (e.g., slot group ID/index, total-DAI, NFI, CTI, informationon whether fallback A/N is required, and/or information on whether thereis pending A/N) and/or b) a specific value (e.g., default value) may beapplied/assumed to/for the information.

In the case of a), the DL grant DCI related to the recentlydetected/received information may be limited only to DCI indicating thata PUSCH transmission time (slot) is equal to a PDSCH HARQ-ACKtransmission. In the case of b), the following assumption may be appliedto at least one of the information.

1) For the total-DAI, it is assumed/applied that the total-DAI bits are11 (or the total-DAI value is 4).

2) For the NFI, it is assumed/applied that the NFI bit is toggled (ornon-toggled) (compared to the previous A/N feedback or previously(recently) received NFI bit).

3) For the CTI, it is assumed/applied that the Type-2a codebook isindicated (or the Type-1 codebook is indicated in the following case).

4) For information on whether A/N feedback is based on the Type-1codebook, it is assumed/applied that the corresponding field/signalingis not present.

5) For the information on whether there is pending A/N, it isassumed/applied that A/N feedback is not pending.

(b) DCI Configuration and Signaling Information in Configuration ofType-1 A/N Codebook

1) Information signaled in DL grant DCI

A. Basically, the following information may be included (basicinformation).

i. Information on whether there is fallback A/N

ii. Notes

1. The information may indicate whether only one piece of fallback DCIscheduling a PCell (or PDSCH transmission thereon) is transmitted withinone bundling window. The information may be configured/signaled withonly 1 bit.

B. Additionally, the following information may be further included.

i. Information on whether A/N feedback is configured/transmitted basedon the Type-3 codebook (e.g., a CTI indicating which one of the Type-1and Type-3 A/N codebooks is used)

ii. Notes

1. If Type-3 is indicated by DCI (at a specific time), information aboutan NFI related to A/N feedback based on the Type-3 codebook may beadditionally signaled by the corresponding DCI.

C. Additionally, the following information may be further included.

i. Information on whether there is pending A/N

ii. Notes

1. The information may indicate whether final A/N feedback is configuredby further including A/N where pending is indicated (at a previous timepoint) (i.e., pending A/N) in an A/N payload configured based on theType-1 codebook.

D. DL scheduling based on fallback DCI

i. Basically, corresponding DCI formats (at least related to aPCell/PSCell) may include/signal the basic information.

ii. Additionally, fallback DCI formats related to an SCell (except thePCell/PSCell) may not include/signal the basic information.

E. DL transmission operation on CBG basis

i. For a CC/cell where DL transmission is configured on a CBG basis orfor CA including the CC/cell where DL transmission is configured on aCBG basis, the pending A/N payload may be determined based on themaximum number of (transmittable) CBGs configured for all cells/CCs,that is, the maximum of the numbers of (transmittable) CBGs configuredper cell/CC. For a CC/cell where transmission is configured on a TBbasis or for aggregation of only CCs/cells where transmission isconfigured on a TB basis, the pending A/N payload may be determinedbased on the maximum number of (transmittable) TBs configured for allcells/CCs, that is, the maximum of the numbers of (transmittable) TBsconfigured per cell/CC.

2) Information signaled in UL grant DCI

A. Basically, the following information may be included (basicinformation).

i. Information on whether A/N feedback is based on the Type-1 codebook

ii. Notes

1. The information may indicate whether the A/N payload configured basedon the Type-1 codebook is transmitted through piggyback on the PUSCH (itmay be further indicated whether only fallback A/N is piggybacked orzero bits are transmitted (piggyback drop)).

B. Additionally, the following information may be further included.

i. Information on whether A/N feedback is configured/transmitted basedon the Type-3 codebook (e.g., information on which one of the Type-2aand Type-3 A/N codebooks is used)

ii. Notes

1. If Type-3 is indicated by DCI (at a specific time), information aboutan NFI related to A/N feedback based on the Type-3 codebook may beadditionally signaled by the corresponding DCI.

C. Additionally, the following information may be further included.

i. Information on whether there is pending A/N

ii. Notes

1. The information may indicate whether final A/N feedback is configuredby further including A/N where pending is indicated (at a previous timepoint) (i.e., pending A/N) in the A/N payload configured based on theType-1 codebook.

D. UL scheduling based on fallback DCI

i. Basically, fallback DCI formats may not include/signal the basicinformation.

ii. For information that is not included/signaled by the UL grant DCI,the UE may configure/transmit an A/N codebook (payload) based on themost recently detected/received information from the DL grant DCI (e.g.,information on whether there is fallback A/N, CTI, information onwhether there is pending A/N, etc.). In this case, the DL grant DCIrelated to the recently detected/received information may be limitedonly to DCI indicating the same PDSCH HARQ-ACK transmission time as aPUSCH transmission time (or slot) scheduled by the UL grant DCI.

iii. A/N may be piggybacked on the CG-PUSCH, which is transmitted in theform of a CG without DCI, instead of scheduling with dynamic grant DCItransmission. In this case, the UE may configure/transmit an A/Ncodebook (payload) based on the most recently detected/receivedinformation from the DL grant DCI (e.g., information on whether there isfallback A/N, CTI, information on whether there is pending A/N, etc.).The DL grant DCI related to the recently detected/received informationmay be limited only to DCI indicating the same PDSCH HARQ-ACKtransmission time as a CG-PUSCH transmission time (slot).

E. DL transmission operation on CBG basis

i. Similarly to the above-described DL grant DCI case, the pending A/Npayload may be determined based on the maximum number of (transmittable)CBGs or TBs configured for all cells/CCs.

The DL/UL grant DCI configuration and signaling operation (based on theType-2a or Type-1 A/N codebook configuration) (including the Type-2a orType-1 A/N codebook configuration) may be applied only to a PUCCHcell/CC configured for PUSCCH transmission in the CA environment (e.g.,PCell or PSCell) operates in a U-band. In this case, DL/UL grant DCIrelated to all cells/CCs for the CA may be configured according to themethods proposed in the present disclosure. If the PUCCH cell/CCoperates in an L-band, the conventional DL/UL grant DCI configurationand signaling operation may be applied (if the conventional Type-1 orType-2 A/N codebook is configured). In this case, DL/UL grant DCIrelated to all aggregated cells/CCs may be the same as in the prior art.

As another method, the Type-2a or Type-1 A/N codebook configuration andthe DL/UL grant DCI configuration/signaling based thereon may be appliedonly when a cell/CC operating in a U-band is included in multiplecarriers configured for the UE, i.e., a set of cells/CCs configured forthe CA. In this case, DL/UL grant DCI related to all aggregatedcells/CCs may be configured according to the proposed methods. When themultiple carriers consist of only cells/CCs operating in L-bands, theconventional Type-1 or Type-2 A/N codebook configuration and theconventional DL/UL grant DCI configuration/signaling based thereon maybe applied. In this case, DL/UL grant DCI related to all aggregatedcells/CCs may be the same as in the prior art.

The UE may perform a network access process to perform theabove-described/proposed procedures and/or methods. For example, the UEmay receive and store system information and configuration informationrequired to perform the above-described/proposed procedures and/ormethods during network access (e.g., BS access). The configurationinformation required for the present disclosure may be received byhigher-layer signaling (e.g., RRC signaling or MAC-layer signaling).

FIG. 16 is a diagram illustrating an initial network access andsubsequent communication process. In NR, a physical channel and an RSmay be transmitted by beamforming. When beamforming-based signaltransmission is supported, beam management may follow, for beamalignment between a BS and a UE. Further, a signal proposed by thepresent disclosure may be transmitted/received by beamforming. In RRCIDLE mode, beam alignment may be performed based on an SSB, whereas inRRC CONNECTED mode, beam alignment may be performed based on a CSI-RS(in DL) and an SRS (in UL). On the contrary, when beamforming-basedsignal transmission is not supported, beam-related operations in thefollowing description may be skipped.

Referring to FIG. 16, a BS (e.g., eNB) may periodically transmit an SSB(S702). The SSB includes a PSS/SSS/PBCH. The SSB may be transmitted bybeam sweeping (see FIG. D5). The PBCH may include a master informationblock (MSB), and the MIB may include scheduling information forremaining minimum system information (RMSI). The BS may then transmitthe RMSI and other system information (OSI) (S704). The RMSI may includeinformation required for initial access to the BS (e.g., PRACHconfiguration information). After detecting SSBs, the UE identifies thebest SSB. The UE may then transmit an RACH preamble (Message 1; Msg1) inPRACH resources linked/corresponding to the index (i.e., beam) of thebest SSB (S706). The beam direction of the RACH preamble is associatedwith the PRACH resources. Association between PRACH resources (and/orRACH preambles) and SSBs (SSB indexes) may be configured by systeminformation (e.g., RMSI). Subsequently, in an RACH procedure, the BS maytransmit a random access response (RAR) (Msg2) in response to the RACHpreamble (S708), the UE may transmit Msg3 (e.g., RRC Connection Request)based on a UL grant included in the RAR (S710), and the BS may transmita contention resolution message (Msg4) (S720). Msg4 may include RRCConnection Setup.

When an RRC connection is established between the BS and the UE in theRACH procedure, beam alignment may subsequently be performed based on anSSB/CSI-RS (in DL) and an SRS (in UL). For example, the UE may receivean SSB/CSI-RS (S714). The SSB/CSI-RS may be used for the UE to generatea beam/CSI report. The BS may request the UE to transmit a beam/CSIreport, by DCI (S716). In this case, the UE may generate a beam/CSIreport based on the SSB/CSI-RS and transmit the generated beam/CSIreport to the BS on a PUSCH/PUCCH (S718). The beam/CSI report mayinclude a beam measurement result, information about a preferred beam,and so on. The BS and the UE may switch beams based on the beam/CSIreport (S720 a and S720 b).

Subsequently, the UE and the BS may perform the above-described/proposedprocedures and/or methods. For example, the UE and the BS may transmit awireless signal by processing information stored in a memory or mayprocess a received wireless signal and store the processed signal in amemory according to the proposal of the present disclosure, based onconfiguration information obtained in a network access process (e.g., asystem information acquisition process, an RRC connection process on anRACH, and so on). The wireless signal may include at least one of aPDCCH, a PDSCH, or an RS on DL and at least one of a PUCCH, a PUSCH, oran SRS on UL.

FIG. 17 illustrates a communication system 1 applied to the presentdisclosure.

Referring to FIG. 17, the communication system 1 applied to the presentdisclosure includes wireless devices, BSs, and a network. A wirelessdevice is a device performing communication using radio accesstechnology (RAT) (e.g., 5G NR (or New RAT) or LTE), also referred to asa communication/radio/5G device. The wireless devices may include, notlimited to, a robot 100 a, vehicles 100 b-1 and 100 b-2, an extendedreality (XR) device 100 c, a hand-held device 100 d, a home appliance100 e, an IoT device 100 f, and an artificial intelligence (AI)device/server 400. For example, the vehicles may include a vehiclehaving a wireless communication function, an autonomous driving vehicle,and a vehicle capable of vehicle-to-vehicle (V2V) communication. Herein,the vehicles may include an unmanned aerial vehicle (UAV) (e.g., adrone). The XR device may include an augmented reality (AR)/virtualreality (VR)/mixed reality (MR) device and may be implemented in theform of a head-mounted device (HMD), a head-up display (HUD) mounted ina vehicle, a television (TV), a smartphone, a computer, a wearabledevice, a home appliance, a digital signage, a vehicle, a robot, and soon. The hand-held device may include a smartphone, a smart pad, awearable device (e.g., a smart watch or smart glasses), and a computer(e.g., a laptop). The home appliance may include a TV, a refrigerator, awashing machine, and so on. The IoT device may include a sensor, a smartmeter, and so on. For example, the BSs and the network may beimplemented as wireless devices, and a specific wireless device 200 amay operate as a BS/network node for other wireless devices.

The wireless devices 100 a to 100 f may be connected to the network 300via the BSs 200. An AI technology may be applied to the wireless devices100 a to 100 f, and the wireless devices 100 a to 100 f may be connectedto the AI server 400 via the network 300. The network 300 may beconfigured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g.,NR) network. Although the wireless devices 100 a to 100 f maycommunicate with each other through the BSs 200/network 300, thewireless devices 100 a to 100 f may perform direct communication (e.g.,sidelink communication) with each other without intervention of theBSs/network. For example, the vehicles 100 b-1 and 100 b-2 may performdirect communication (e.g. V2V/vehicle-to-everything (V2X)communication). The IoT device (e.g., a sensor) may perform directcommunication with other IoT devices (e.g., sensors) or other wirelessdevices 100 a to 100 f.

Wireless communication/connections 150 a, 150 b, and 150 c may beestablished between the wireless devices 100 a to 100 f/BS 200 andbetween the BSs 200. Herein, the wireless communication/connections maybe established through various RATs (e.g., 5G NR) such as UL/DLcommunication 150 a, sidelink communication 150 b (or, D2Dcommunication), or inter-BS communication (e.g. relay or integratedaccess backhaul (IAB)). Wireless signals may be transmitted and receivedbetween the wireless devices, between the wireless devices and the BSs,and between the BSs through the wireless communication/connections 150a, 150 b, and 150 c. For example, signals may be transmitted and receivedon various physical channels through the wirelesscommunication/connections 150 a, 150 b and 150 c. To this end, at leasta part of various configuration information configuring processes,various signal processing processes (e.g., channel encoding/decoding,modulation/demodulation, and resource mapping/demapping), and resourceallocation processes, for transmitting/receiving wireless signals, maybe performed based on the various proposals of the present disclosure.

FIG. 18 illustrates wireless devices applicable to the presentdisclosure.

Referring to FIG. 18, a first wireless device 100 and a second wirelessdevice 200 may transmit wireless signals through a variety of RATs(e.g., LTE and NR). {The first wireless device 100 and the secondwireless device 200} may correspond to {the wireless device 100 x andthe BS 200} and/or {the wireless device 100 x and the wireless device100 x} of FIG. 18.

The first wireless device 100 may include one or more processors 102 andone or more memories 104, and further include one or more transceivers106 and/or one or more antennas 108. The processor(s) 102 may controlthe memory(s) 104 and/or the transceiver(s) 106 and may be configured toimplement the descriptions, functions, procedures, proposals, methods,and/or operation flowcharts disclosed in this document. For example, theprocessor(s) 102 may process information in the memory(s) 104 togenerate first information/signals and then transmit wireless signalsincluding the first information/signals through the transceiver(s) 106.The processor(s) 102 may receive wireless signals including secondinformation/signals through the transceiver(s) 106 and then storeinformation obtained by processing the second information/signals in thememory(s) 104. The memory(s) 104 may be connected to the processor(s)102 and may store various pieces of information related to operations ofthe processor(s) 102. For example, the memory(s) 104 may store softwarecode including instructions for performing all or a part of processescontrolled by the processor(s) 102 or for performing the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document. The processor(s) 102 and the memory(s) 104may be a part of a communication modem/circuit/chip designed toimplement RAT (e.g., LTE or NR). The transceiver(s) 106 may be connectedto the processor(s) 102 and transmit and/or receive wireless signalsthrough the one or more antennas 108. Each of the transceiver(s) 106 mayinclude a transmitter and/or a receiver. The transceiver(s) 106 may beinterchangeably used with radio frequency (RF) unit(s). In the presentdisclosure, the wireless device may be a communicationmodem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204, and further include one or moretransceivers 206 and/or one or more antennas 208. The processor(s) 202may control the memory(s) 204 and/or the transceiver(s) 206 and may beconfigured to implement the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument. For example, the processor(s) 202 may process information inthe memory(s) 204 to generate third information/signals and thentransmit wireless signals including the third information/signalsthrough the transceiver(s) 206. The processor(s) 202 may receivewireless signals including fourth information/signals through thetransceiver(s) 106 and then store information obtained by processing thefourth information/signals in the memory(s) 204. The memory(s) 204 maybe connected to the processor(s) 202 and store various pieces ofinformation related to operations of the processor(s) 202. For example,the memory(s) 204 may store software code including instructions forperforming all or a part of processes controlled by the processor(s) 202or for performing the descriptions, functions, procedures, proposals,methods, and/or operation flowcharts disclosed in this document. Theprocessor(s) 202 and the memory(s) 204 may be a part of a communicationmodem/circuit/chip designed to implement RAT (e.g., LTE or NR). Thetransceiver(s) 206 may be connected to the processor(s) 202 and transmitand/or receive wireless signals through the one or more antennas 208.Each of the transceiver(s) 206 may include a transmitter and/or areceiver. The transceiver(s) 206 may be interchangeably used with RFunit(s). In the present disclosure, the wireless device may be acommunication modem/circuit/chip.

Now, hardware elements of the wireless devices 100 and 200 will bedescribed in greater detail. One or more protocol layers may beimplemented by, not limited to, one or more processors 102 and 202. Forexample, the one or more processors 102 and 202 may implement one ormore layers (e.g., functional layers such as physical (PHY), mediumaccess control (MAC), radio link control (RLC), packet data convergenceprotocol (PDCP), RRC, and service data adaptation protocol (SDAP)). Theone or more processors 102 and 202 may generate one or more protocoldata units (PDUs) and/or one or more service data Units (SDUs) accordingto the descriptions, functions, procedures, proposals, methods, and/oroperation flowcharts disclosed in this document. The one or moreprocessors 102 and 202 may generate messages, control information, data,or information according to the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument and provide the messages, control information, data, orinformation to one or more transceivers 106 and 206. The one or moreprocessors 102 and 202 may generate signals (e.g., baseband signals)including PDUs, SDUs, messages, control information, data, orinformation according to the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument and provide the generated signals to the one or moretransceivers 106 and 206. The one or more processors 102 and 202 mayreceive the signals (e.g., baseband signals) from the one or moretransceivers 106 and 206 and acquire the PDUs, SDUs, messages, controlinformation, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document.

The one or more processors 102 and 202 may be referred to ascontrollers, microcontrollers, microprocessors, or microcomputers. Theone or more processors 102 and 202 may be implemented by hardware,firmware, software, or a combination thereof. For example, one or moreapplication specific integrated circuits (ASICs), one or more digitalsignal processors (DSPs), one or more digital signal processing devices(DSPDs), one or more programmable logic devices (PLDs), or one or morefield programmable gate arrays (FPGAs) may be included in the one ormore processors 102 and 202. The descriptions, functions, procedures,proposals, methods, and/or operation flowcharts disclosed in thisdocument may be implemented using firmware or software, and the firmwareor software may be configured to include the modules, procedures, orfunctions. Firmware or software configured to perform the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document may be included in the one or more processors102 and 202 or may be stored in the one or more memories 104 and 204 andexecuted by the one or more processors 102 and 202. The descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdisclosed in this document may be implemented using firmware or softwarein the form of code, an instruction, and/or a set of instructions.

The one or more memories 104 and 204 may be connected to the one or moreprocessors 102 and 202 and store various types of data, signals,messages, information, programs, code, instructions, and/or commands.The one or more memories 104 and 204 may be configured to includeread-only memories (ROMs), random access memories (RAMs), electricallyerasable programmable read-only memories (EPROMs), flash memories, harddrives, registers, cash memories, computer-readable storage media,and/or combinations thereof. The one or more memories 104 and 204 may belocated at the interior and/or exterior of the one or more processors102 and 202. The one or more memories 104 and 204 may be connected tothe one or more processors 102 and 202 through various technologies suchas wired or wireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, and/or wireless signals/channels, mentioned in the methodsand/or operation flowcharts of this document, to one or more otherdevices. The one or more transceivers 106 and 206 may receive user data,control information, and/or wireless signals/channels, mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperation flowcharts disclosed in this document, from one or more otherdevices. For example, the one or more transceivers 106 and 206 may beconnected to the one or more processors 102 and 202 and transmit andreceive wireless signals. For example, the one or more processors 102and 202 may perform control so that the one or more transceivers 106 and206 may transmit user data, control information, or wireless signals toone or more other devices. The one or more processors 102 and 202 mayperform control so that the one or more transceivers 106 and 206 mayreceive user data, control information, or wireless signals from one ormore other devices. The one or more transceivers 106 and 206 may beconnected to the one or more antennas 108 and 208 and the one or moretransceivers 106 and 206 may be configured to transmit and receive userdata, control information, and/or wireless signals/channels, mentionedin the descriptions, functions, procedures, proposals, methods, and/oroperation flowcharts disclosed in this document, through the one or moreantennas 108 and 208. In this document, the one or more antennas may bea plurality of physical antennas or a plurality of logical antennas(e.g., antenna ports). The one or more transceivers 106 and 206 mayconvert received wireless signals/channels from RF band signals intobaseband signals in order to process received user data, controlinformation, and wireless signals/channels using the one or moreprocessors 102 and 202. The one or more transceivers 106 and 206 mayconvert the user data, control information, and wirelesssignals/channels processed using the one or more processors 102 and 202from the baseband signals into the RF band signals. To this end, the oneor more transceivers 106 and 206 may include (analog) oscillators and/orfilters.

FIG. 19 illustrates another example of a wireless device applied to thepresent disclosure. The wireless device may be implemented in variousforms according to a use case/service (refer to FIG. 17).

Referring to FIG. 19, wireless devices 100 and 200 may correspond to thewireless devices 100 and 200 of FIG. 17 and may be configured to includevarious elements, components, units/portions, and/or modules. Forexample, each of the wireless devices 100 and 200 may include acommunication unit 110, a control unit 120, a memory unit 130, andadditional components 140. The communication unit 110 may include acommunication circuit 112 and transceiver(s) 114. For example, thecommunication circuit 112 may include the one or more processors 102 and202 and/or the one or more memories 104 and 204 of FIG. 19. For example,the transceiver(s) 114 may include the one or more transceivers 106 and206 and/or the one or more antennas 108 and 208 of FIG. 19. The controlunit 120 is electrically connected to the communication unit 110, thememory 130, and the additional components 140 and provides overallcontrol to the wireless device. For example, the control unit 120 maycontrol an electric/mechanical operation of the wireless device based onprograms/code/instructions/information stored in the memory unit 130.The control unit 120 may transmit the information stored in the memoryunit 130 to the outside (e.g., other communication devices) via thecommunication unit 110 through a wireless/wired interface or store, inthe memory unit 130, information received through the wireless/wiredinterface from the outside (e.g., other communication devices) via thecommunication unit 110.

The additional components 140 may be configured in various mannersaccording to type of the wireless device. For example, the additionalcomponents 140 may include at least one of a power unit/battery,input/output (I/O) unit, a driving unit, and a computing unit. Thewireless device may be implemented in the form of, not limited to, therobot (100 a of FIG. 17), the vehicles (100 b-1 and 100 b-2 of FIG. 17),the XR device (100 c of FIG. 17), the hand-held device (100 d of FIG.17), the home appliance (100 e of FIG. 17), the IoT device (100 f ofFIG. 17), a digital broadcasting terminal, a hologram device, a publicsafety device, an MTC device, a medical device, a FinTech device (or afinance device), a security device, a climate/environment device, the AIserver/device (400 of FIG. 17), the BSs (200 of FIG. 17), a networknode, or the like. The wireless device may be mobile or fixed accordingto a use case/service.

In FIG. 19, all of the various elements, components, units/portions,and/or modules in the wireless devices 100 and 200 may be connected toeach other through a wired interface or at least a part thereof may bewirelessly connected through the communication unit 110. For example, ineach of the wireless devices 100 and 200, the control unit 120 and thecommunication unit 110 may be connected by wire and the control unit 120and first units (e.g., 130 and 140) may be wirelessly connected throughthe communication unit 110. Each element, component, unit/portion,and/or module in the wireless devices 100 and 200 may further includeone or more elements. For example, the control unit 120 may beconfigured with a set of one or more processors. For example, thecontrol unit 120 may be configured with a set of a communication controlprocessor, an application processor, an electronic control unit (ECU), agraphical processing unit, and a memory control processor. In anotherexample, the memory 130 may be configured with a RAM, a dynamic RAM(DRAM), a ROM, a flash memory, a volatile memory, a non-volatile memory,and/or a combination thereof.

FIG. 20 illustrates a vehicle or an autonomous driving vehicle appliedto the present disclosure. The vehicle or autonomous driving vehicle maybe implemented as a mobile robot, a car, a train, a manned/unmannedaerial vehicle (AV), a ship, or the like.

Referring to FIG. 20, a vehicle or autonomous driving vehicle 100 mayinclude an antenna unit 108, a communication unit 110, a control unit120, a driving unit 140 a, a power supply unit 140 b, a sensor unit 140c, and an autonomous driving unit 140 d. The antenna unit 108 may beconfigured as a part of the communication unit 110. The blocks110/130/140 a to 140 d correspond to the blocks 110/130/140 of FIG. 19,respectively.

The communication unit 110 may transmit and receive signals (e.g., dataand control signals) to and from external devices such as othervehicles, BSs (e.g., gNBs and road side units), and servers. The controlunit 120 may perform various operations by controlling elements of thevehicle or the autonomous driving vehicle 100. The control unit 120 mayinclude an ECU. The driving unit 140 a may enable the vehicle or theautonomous driving vehicle 100 to drive on a road. The driving unit 140a may include an engine, a motor, a powertrain, a wheel, a brake, asteering device, and so on. The power supply unit 140 b may supply powerto the vehicle or the autonomous driving vehicle 100 and include awired/wireless charging circuit, a battery, and so on. The sensor unit140 c may acquire information about a vehicle state, ambient environmentinformation, user information, and so on. The sensor unit 140 c mayinclude an inertial measurement unit (IMU) sensor, a collision sensor, awheel sensor, a speed sensor, a slope sensor, a weight sensor, a headingsensor, a position module, a vehicle forward/backward sensor, a batterysensor, a fuel sensor, a tire sensor, a steering sensor, a temperaturesensor, a humidity sensor, an ultrasonic sensor, an illumination sensor,a pedal position sensor, and so on. The autonomous driving unit 140 dmay implement technology for maintaining a lane on which the vehicle isdriving, technology for automatically adjusting speed, such as adaptivecruise control, technology for autonomously driving along a determinedpath, technology for driving by automatically setting a route if adestination is set, and the like.

For example, the communication unit 110 may receive map data, trafficinformation data, and so on from an external server. The autonomousdriving unit 140 d may generate an autonomous driving route and adriving plan from the obtained data. The control unit 120 may controlthe driving unit 140 a such that the vehicle or autonomous drivingvehicle 100 may move along the autonomous driving route according to thedriving plan (e.g., speed/direction control). During autonomous driving,the communication unit 110 may aperiodically/periodically acquire recenttraffic information data from the external server and acquiresurrounding traffic information data from neighboring vehicles. Duringautonomous driving, the sensor unit 140 c may obtain information about avehicle state and/or surrounding environment information. The autonomousdriving unit 140 d may update the autonomous driving route and thedriving plan based on the newly obtained data/information. Thecommunication unit 110 may transfer information about a vehicleposition, the autonomous driving route, and/or the driving plan to theexternal server. The external server may predict traffic informationdata using AI technology based on the information collected fromvehicles or autonomous driving vehicles and provide the predictedtraffic information data to the vehicles or the autonomous drivingvehicles.

The above-described embodiments are combinations of elements andfeatures of the present disclosure in prescribed forms. The elements orfeatures may be considered as selective unless specified otherwise. Eachelement or feature may be implemented without being combined with otherelements or features. Further, the embodiment of the present disclosuremay be constructed by combining some of the elements and/or features.The order of the operations described in the embodiments of the presentdisclosure may be modified. Some configurations or features of any oneembodiment may be included in another embodiment or replaced withcorresponding configurations or features of the other embodiment. It isobvious to those skilled in the art that claims that are not explicitlycited in each other in the appended claims may be presented incombination as an embodiment of the present disclosure or included as anew claim by a subsequent amendment after the application is filed.

It will be appreciated by those skilled in the art that the presentdisclosure can be carried out in other specific ways than those setforth herein without departing from the essential characteristics of thepresent disclosure. The above embodiments are therefore to be construedin all aspects as illustrative and not restrictive. The scope of thedisclosure should be determined by the appended claims and their legalequivalents, not by the above description, and all changes coming withinthe meaning and equivalency range of the appended claims are intended tobe embraced therein.

The present disclosure is applicable to a UE, a BS, or other devices ofa wireless mobile communication system.

1-15. (canceled)
 16. A method for transmitting a signal by an apparatusin wireless communication system, the method comprising: receiving firstDownlink Control Information (DCI) including a first counter-DownlinkAssignment Index (DAI) related to a first Physical Downlink SharedChannel (PDSCH) group for a first PDSCH; receiving the first PDSCH basedon the first DCI; receiving second DCI including a second counter-DAIrelated to a second PDSCH group for a second PDSCH; receiving the secondPDSCH based on the second DCI; receiving third DCI including a firsttotal-DAI for the first PDSCH group and a second total-DAI for thesecond PDSCH group; and transmitting Uplink Control Information (UCI)including a first Acknowledgement/Negative acknowledgement (A/N) for thefirst PDSCH group based on the first total-DAI and a second A/N for thesecond PDSCH group based on the second total-DAI.
 17. The method ofclaim 16, wherein the third DCI does not include identificationinformation for the first PDSCH group and the second PDSCH group,wherein the first DCI includes identification information for the firstPDSCH group, and wherein the second DCI includes identificationinformation for the second PDSCH group.
 18. The method of claim 16,wherein the second DCI includes a third total-DAI for the first PDSCHgroup.
 19. The method of claim 16, wherein the second DCI includes aforth total-DAI for the second PDSCH group.
 20. The method of claim 16,wherein the second DCI includes information related to a transmissiontiming of the UCI.
 21. The method of claim 16, wherein the UCI istransmitted via an unlicensed band.
 22. An apparatus for transmitting asignal in wireless communication system, the apparatus comprising: atleast one processor; and at least one computer memory operablyconnectable to the at least one processor and storing instructions that,when executed by the at least one processor, perform operationscomprising: receiving first Downlink Control Information (DCI) includinga first counter-Downlink Assignment Index (DAI) related to a firstPhysical Downlink Shared Channel (PDSCH) group for a first PDSCH;receiving the first PDSCH based on the first DCI; receiving second DCIincluding a second counter-DAI related to a second PDSCH group for asecond PDSCH; receiving the second PDSCH based on the second DCI;receiving third DCI including a first total-DAI for the first PDSCHgroup and a second total-DAI for the second PDSCH group; andtransmitting Uplink Control Information (UCI) including a firstAcknowledgement/Negative acknowledgement (A/N) for the first PDSCH groupbased on the first total-DAI and a second A/N for the second PDSCH groupbased on the second total-DAI.
 23. The apparatus of claim 22, whereinthe third DCI does not include identification information for the firstPDSCH group and the second PDSCH group, wherein the first DCI includesidentification information for the first PDSCH group, and wherein thesecond DCI includes identification information for the second PDSCHgroup.
 24. The apparatus of claim 22, wherein the second DCI includes athird total-DAI for the first PDSCH group.
 25. The apparatus of claim22, wherein the second DCI includes a forth total-DAI for the secondPDSCH group.
 26. The apparatus of claim 22, wherein the second DCIincludes information related to a transmission timing of the UCI. 27.The apparatus of claim 22, wherein the UCI is transmitted via anunlicensed band.
 28. The apparatus of claim 22, wherein the apparatuscommunicates with at least one of a user equipment (UE), a base station,a network, or an autonomous driving vehicle.